diff --git a/Makefile b/Makefile
index 3332948..997c741 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-# WarpEngine Store GUI — the front door to the npm scripts.
+# WarpEngine Client — the front door to the npm scripts.
 #
 # Everything here is a thin wrapper: the app is an Electron project, so npm still
 # does the work. The Makefile exists so the useful sequences have names, and so
@@ -22,13 +22,23 @@ NODE_MIN := 22
 VERSION := $(shell python3 -c 'import json; print(json.load(open("package.json"))["version"])')
 TAG ?= v$(VERSION)
 
+# Which site's store registry a packaged build reads. Empty means the default in
+# package.json (ours); set it to build a client for somebody else's catalog:
+#
+#   make dist STORES_API=https://games.example.org/api/stores
+#
+# It is baked into the package's own package.json, so the built app carries it. A runtime
+# STORES_API still overrides it, which is for trying something out rather than shipping.
+STORES_API ?=
+BUILDER_ARGS := $(if $(STORES_API),-- --config.extraMetadata.warpEngine.registryUrl=$(STORES_API),)
+
 .DEFAULT_GOAL := help
 
 .PHONY: help setup node-check build typecheck lint lint-fix check start smoke uitest test \
         dist dist-mac dist-win dist-linux release publish clean distclean version
 
 help: ## List available targets
-	@echo "WarpEngine Store GUI $(VERSION) — usage: make <target>"
+	@echo "WarpEngine Client $(VERSION) — usage: make <target>"
 	@echo
 	@grep -E '^[a-zA-Z_-]+:.*?## ' $(MAKEFILE_LIST) | \
 		awk 'BEGIN {FS = ":.*?## "}; {printf "  %-12s %s\n", $$1, $$2}'
@@ -74,16 +84,16 @@ uitest: ## Load the window once and report what rendered
 test: smoke uitest ## Both checks
 
 dist: node-check ## Package for this machine
-	npm run dist
+	npm run dist $(BUILDER_ARGS)
 
 dist-mac: node-check ## Package for macOS (ad-hoc signed, see the README)
-	npm run dist:mac
+	npm run dist:mac $(BUILDER_ARGS)
 
 dist-win: node-check ## Package for Windows
-	npm run dist:win
+	npm run dist:win $(BUILDER_ARGS)
 
 dist-linux: node-check ## Package for Linux
-	npm run dist:linux
+	npm run dist:linux $(BUILDER_ARGS)
 
 publish: ## Upload the packages already in dist/ to the Gitea release
 	@TAG=$(TAG) $(SCRIPTS)/release.sh
@@ -107,3 +117,5 @@ version: ## Show the versions involved
 	@printf "eslint     "; npx eslint --version 2>/dev/null || echo "missing"
 	@printf "tea        "; tea --version 2>/dev/null | head -1 || echo "missing — devarea: make tea"
 	@printf "python3    "; python3 --version 2>/dev/null || echo "missing"
+	@printf "registry   "; python3 -c 'import json; print(json.load(open("package.json"))["warpEngine"]["registryUrl"])'
+	@if [ -n "$(STORES_API)" ]; then printf "  build override: %s\n" "$(STORES_API)"; fi
diff --git a/README.md b/README.md
index 08c25e2..5677813 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# warp-engine-client — the WarpEngine Store app
+# warp-engine-client — the WarpEngine Client app
 
 The graphical client for a WarpEngine store — the app is called **WarpEngine
 Store** — driving
@@ -41,7 +41,7 @@ The build is ad-hoc signed but **not notarised**, so macOS asks before running a
 copy that came from a browser. The reliable way through:
 
 ```sh
-xattr -dr com.apple.quarantine "/Applications/WarpEngine Store.app"
+xattr -dr com.apple.quarantine "/Applications/WarpEngine Client.app"
 ```
 
 If macOS offers *Open Anyway* under **System Settings ▸ Privacy & Security** after
@@ -98,13 +98,19 @@ What the defaults produce, for a record with no repository: the games land in a
 folder named after the store id, and released, archived **and demo** titles are
 listed — a catalog that publishes a demo means it to be played.
 
-The registry address is the single thing about a particular site left in the
-client, and `STORES_API` overrides it:
+The registry address is the single thing about a particular site left in the client,
+and it is decided in three places, most specific first:
 
 ```sh
-STORES_API=http://127.0.0.1:8731/stores npm start
+STORES_API=http://127.0.0.1:8731/stores npm start   # runtime: for trying something out
+make dist STORES_API=https://games.example.org/api/stores   # build: for shipping it
 ```
 
+The build variant is baked into the packaged app's own `package.json`
+(`warpEngine.registryUrl`, written by `electron-builder --config.extraMetadata`), so a
+client built for somebody else's catalog needs no source change and no environment on the
+user's machine. With neither set, the address is ours.
+
 Adding a store is therefore a database row on the site — see its ActiveAdmin
 panel — and not a release of this app.
 
@@ -139,6 +145,14 @@ once it is there. **Remove** takes a title back out. Each card says whether it i
 build the catalog serves rather than packages, so its entry opens a page and needs
 the network.
 
+**Everything in the catalog is listed, including what this machine cannot install.**
+Those cards are dimmed, carry an *unsupported platform* or *no build for this machine*
+badge with the engine's own explanation under it, and have nothing to press. A store
+that hides them leaves you wondering whether the catalog is small or your machine is
+unusual; this way it says which. They have a category of their own — *Not for this
+machine* — and they are left out of the native/hosted counts, because a title with no
+build has no mode to be counted under.
+
 Every card carries a band of box art the same height — the first letter of the
 title when the catalog has no image — so titles and buttons line up across a row.
 Until this was photographed, the grid was quietly broken: the rows split the
@@ -261,7 +275,7 @@ on its own: publishing 1.2.0 got *"invalid username, password or token"* on the
 second package while the first had just gone up with the same token, and the same
 command succeeded immediately afterwards.
 
-Package names contain a space — `WarpEngine Store-1.2.0-arm64.dmg` — so the list of
+Package names contain a space — `WarpEngine Client-1.5.0-arm64.dmg` — so the list of
 files is passed one path per line rather than as one string; splitting it on
 whitespace is what broke the first attempt at publishing 1.1.0.
 
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index 09d5139..ca83ed7 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -1,90 +1,55 @@
-# WarpEngine Store 1.4.0
+# WarpEngine Client 1.5.0
 
-**A store no longer needs a repository of its own.** Until now every store in the
-registry pointed at a repository holding its `config.json`, and the client read that
-file to know what to install. It turns out almost nothing in there was necessary: the
-store engine's built-in defaults already cover the host-to-asset mapping, the install
-modes, the platforms and the behaviour. What defaults cannot know is *identity* — a
-slug, a name and a catalog URL — and that is exactly what a registry record carries.
+**The app is called WarpEngine Client.** It was WarpEngine Store, which named the thing
+it opens rather than the thing you run — and the store is a catalog on a site, not a
+window on your machine. The window title, the packages, the bundle and the menu entry all
+say Client now; the repository already did. The store the window is driving is named in
+the side menu, so the bar no longer repeats it as a badge.
 
-So `storeRepositoryUrl` is now optional. A record with a name and a catalog URL is a
-complete store: the client derives the slug from the catalog host
-(`teletypegames.org` → `teletypegames`), writes a small config and installs. Given a
-repository it still reads it, and that file remains the authority on how the store
-behaves — which platforms it offers, which statuses it shows, where things land. A
-repository without a `config.json` is treated as no repository at all.
+**Every title in the catalog is listed, including the ones this machine cannot install.**
+A C64 cartridge on a desktop, or a game with no build for your operating system, used to
+be silently absent — leaving you to wonder whether the catalog is small or your machine
+is unusual. Those cards are now there, dimmed, with an *unsupported platform* or *no
+build for this machine* badge and the engine's own sentence underneath, and with nothing
+to press. They have a category of their own, *Not for this machine*, and they stay out of
+the native/hosted counts: a title with no build has no mode to be counted under.
 
-With the defaults, games land in a folder named after the store id and released,
-archived **and demo** titles are listed: a catalog that publishes a demo means it to
-be played.
+This needs store engine **1.2.0** (desktop) on **warpstore 1.4.0**, which report what
+they had to leave out and why. An older engine still works — its listing is simply all
+installable, as it was before.
 
-The site's registry endpoint changed to match — `storeRepositoryUrl` answers `null`
-when there is none — and adding a store is now genuinely one database row with two
-fields filled in.
+**A build can be pointed at another site's registry.**
 
-**The "Install all" button is gone.** Titles are installed one at a time from their
-own cards.
+```sh
+make dist STORES_API=https://games.example.org/api/stores
+```
 
-**No footer.** The window carried a bar at the bottom at all times — a toggle and a
-line of absolute paths — for something most sessions never need. The log is still
-there, with the two folder buttons in it, but it lives behind a quiet switch at the
-bottom of the side menu and takes no room until it is opened. The grid gets the height
-back.
+The address is written into the packaged app's own `package.json`, so a client built for
+somebody else's catalog needs no source change and nothing set on the user's machine. A
+runtime `STORES_API` still wins, which is for trying something out rather than shipping.
 
-**The repository is now `warp-engine-client`.** The app has always been called
-WarpEngine Store; `warp-engine-desktop-gui` described the role rather than the
-product, and the host-specific engines keep their own shape
-(`warp-engine-desktop-store`, `-retroarch-store`, `-batocera-store`). Gitea keeps a
-redirect from the old path, and the releases and tags moved with the repository, so
-existing links and clones still resolve.
+### Also
 
-### Three things a screenshot found
-
-Photographing the setup screen — which no automated count had ever looked at — turned
-up three faults that every check had passed:
-
-- the store badge in the bar rendered as an empty pill when no store was open;
-- the gate's store picker showed as an empty dropdown stub, because an explicit
-  `display` in the stylesheet beats the browser's own `[hidden]` rule;
-- the gate went up while the *"No installable titles in the catalog"* line stayed on
-  screen underneath it.
-
-The last one was a design fault, not a typo: whether the gate is up was an imperative
-call on a view rather than state, so the gate and the grid could disagree. The setup
-screen is now a field in the state store, and that one field decides which of the two
-is drawn. The window test's gate assertion was wrong too — it demanded a store picker,
-which only appears when the registry offers more than one store, so a perfectly good
-window failed it.
-
-### Linux and Windows packages now come from CI
-
-A `vX.Y.Z` tag now starts the pipeline, which builds the AppImage, the deb, the NSIS
-installer and the portable exe — Windows through Wine — **creates this release** and
-attaches all four. macOS stays a local build, because Apple's toolchain and its signing
-exist only on a Mac, so `make release` from a Mac pushes that package onto the same
-release afterwards. Publishing uses a `gitea_token` repository secret in Woodpecker.
-
-The Windows installer is not signed: Windows will warn about an unknown publisher until
-there is a certificate.
+The scrollbars are the window's own now: the platform's light track down the side menu of
+a dark window looked like a mistake.
 
 ### Opening it on macOS
 
 Ad-hoc signed, **not notarised**, so macOS asks first:
 
 ```sh
-xattr -dr com.apple.quarantine "/Applications/WarpEngine Store.app"
+xattr -dr com.apple.quarantine "/Applications/WarpEngine Client.app"
 ```
 
 ### What is attached
 
-The macOS arm64 package, built and verified here, plus whatever the pipeline attaches
-for Linux (AppImage, deb) and Windows (installer, portable).
+The macOS package, built and verified on a Mac, plus the Linux (AppImage, deb) and
+Windows (installer, portable) packages the pipeline builds when the tag is pushed.
 
 ### Verified
 
-A repository-less store was installed end to end against a local registry serving one
-record with `storeRepositoryUrl: null`: the id came out as `teletypegames`, the engine
-and the shared core downloaded, the written config had three sections, engine 1.1.0
-accepted it, it listed the same ten titles the configured store does, and a hosted
-title synced into a sandbox with its menu entry written. `make check` is clean, and
-the setup gate was photographed on a machine with no store at all.
+`make check` is clean. The store on this machine lists 13 titles — ten installable, three
+C64 cartridges this store does not carry — and the window was photographed with all
+thirteen on screen, the three dimmed and labelled. The engine change was measured through
+the CLI as well, in both its human and its `--json` listing, and the other two store
+engines still get the two-value answer they ask for.
diff --git a/STRUCTURE.md b/STRUCTURE.md
index 3074bea..6e78a14 100644
--- a/STRUCTURE.md
+++ b/STRUCTURE.md
@@ -62,6 +62,7 @@ src/
     mappers/                  engine JSON → domain
     http/                     HttpTextClient, HttpStatusError
     json/                     JsonRecord: reading data that came from elsewhere
+    config/                   BuildConfiguration: what was decided when this was packaged
     electron/                 ApplicationEnvironment and GameLauncher adapters
   main/
     main.ts                   the entry point: one line of work
@@ -184,6 +185,14 @@ never calls the bridge.
 type, so a typo is a compile error and adding an entry is the whole change. This is
 the extension point for a second engine.
 
+### Build-time configuration
+
+`infrastructure/config/BuildConfiguration.ts` reads the packaged `package.json`, which is
+where a build records the registry it was made for (`warpEngine.registryUrl`, set by
+`make dist STORES_API=…`). Precedence is runtime environment, then build, then the
+built-in default — most specific first, and each one is a different audience: someone
+trying it out, someone shipping a client for another site, us.
+
 ### Untrusted-data readers
 
 Anything parsed from outside — engine stdout, the registry — goes through
diff --git a/package.json b/package.json
index 15cc99a..7d0d6fb 100644
--- a/package.json
+++ b/package.json
@@ -1,8 +1,8 @@
 {
   "name": "warp-engine-client",
-  "productName": "WarpEngine Store",
-  "version": "1.4.0",
-  "description": "Graphical client for a WarpEngine desktop store: install the catalog into your own application menu.",
+  "productName": "WarpEngine Client",
+  "version": "1.5.0",
+  "description": "Graphical client for WarpEngine stores: install a catalog into your own application menu.",
   "license": "MIT",
   "author": "Teletype Games <games@teletype.hu>",
   "homepage": "https://git.teletypegames.org/stores/warp-engine-client",
@@ -34,7 +34,7 @@
   },
   "build": {
     "appId": "org.teletypegames.warpstore.gui",
-    "productName": "WarpEngine Store",
+    "productName": "WarpEngine Client",
     "files": [
       "build/**/*",
       "package.json"
@@ -64,5 +64,8 @@
   "allowScripts": {
     "electron@43.4.0": true,
     "esbuild@0.28.2": true
+  },
+  "warpEngine": {
+    "registryUrl": "https://teletypegames.org/api/stores"
   }
 }
diff --git a/scripts/ci-upload.sh b/scripts/ci-upload.sh
index 639a2ca..4679928 100755
--- a/scripts/ci-upload.sh
+++ b/scripts/ci-upload.sh
@@ -53,7 +53,7 @@ api() {
   curl -fsS -X "$method" -H "$AUTH" "$FORGE$path" "$@"
 }
 
-# Package names contain spaces — "WarpEngine Store Setup 1.4.0.exe" does — so the list
+# Package names contain spaces — "WarpEngine Client Setup 1.5.0.exe" does — so the list
 # lives one path per line in a file and is read with `while IFS= read -r`. A single
 # variable looped over with $list splits on the space and uploads nothing.
 LIST="$(mktemp)"
diff --git a/scripts/release.sh b/scripts/release.sh
index 69e3e18..2fc2c3a 100755
--- a/scripts/release.sh
+++ b/scripts/release.sh
@@ -52,7 +52,7 @@ REPO="${REPO:-$(git remote get-url origin 2>/dev/null |
 #
 #   - the version filter, because dist/ keeps whatever earlier builds left there
 #     and a release would quietly get the previous version's files attached;
-#   - the spaces. "WarpEngine Store-1.1.0-arm64.dmg" has one, so the list lives one
+#   - the spaces. "WarpEngine Client-1.5.0-arm64.dmg" has one, so the list lives one
 #     path per line in a file and is read with `while IFS= read -r`. Holding it in
 #     a single variable and looping over $list splits it on the space.
 LIST="$(mktemp)"
diff --git a/src/application/mappers/GameDtoMapper.ts b/src/application/mappers/GameDtoMapper.ts
index 8ab4b29..1a763b7 100644
--- a/src/application/mappers/GameDtoMapper.ts
+++ b/src/application/mappers/GameDtoMapper.ts
@@ -26,7 +26,10 @@ export class GameDtoMapper {
       installed: game.installed,
       updateAvailable: game.updateAvailable,
       installedVersion: game.installedVersion,
-      launchable: this.isLaunchable(game)
+      launchable: this.isLaunchable(game),
+      installable: game.installable,
+      unavailableReason: game.unavailableReason,
+      unavailableDetail: game.unavailableDetail
     }
   }
 
diff --git a/src/domain/models/Game.ts b/src/domain/models/Game.ts
index 1ad4474..51382fa 100644
--- a/src/domain/models/Game.ts
+++ b/src/domain/models/Game.ts
@@ -1,6 +1,15 @@
 /** How a title runs: unpacked on this machine, or served as a web build. */
 export type GameMode = 'app' | 'web'
 
+/**
+ * Why a title cannot be installed here, as the engine codes it.
+ *
+ * `platformOff` is the store not carrying that platform at all — a C64 cartridge on a
+ * desktop — and the other three are about this machine or this catalog: no asset kind
+ * for the os and architecture, no release carrying it, or the adapter refusing it.
+ */
+export type UnavailableReason = 'platformOff' | 'hostAsset' | 'noAsset' | 'vetoed'
+
 /**
  * A catalog entry, with what the store did about it on this machine.
  *
@@ -24,4 +33,12 @@ export interface Game {
   readonly menuEntryPath: string | null
   readonly executablePath: string | null
   readonly hostedUrl: string | null
+  /**
+   * False for a title this machine cannot install. It is still listed: a catalog that
+   * hides what your machine cannot run leaves you wondering which of the two is small.
+   */
+  readonly installable: boolean
+  readonly unavailableReason: UnavailableReason | null
+  /** The engine's sentence for it, for a tooltip or the log. */
+  readonly unavailableDetail: string | null
 }
diff --git a/src/infrastructure/config/BuildConfiguration.ts b/src/infrastructure/config/BuildConfiguration.ts
new file mode 100644
index 0000000..46289fa
--- /dev/null
+++ b/src/infrastructure/config/BuildConfiguration.ts
@@ -0,0 +1,49 @@
+import fs from 'node:fs'
+import path from 'node:path'
+import { asRecord, readRecord, readString } from '../json/JsonRecord'
+
+/**
+ * What was decided when this package was built.
+ *
+ * The registry address is the one thing about a particular site left in the client, and
+ * a build for a different site should not need a different source tree. So it is a field
+ * in `package.json`, which `electron-builder` can overwrite at packaging time:
+ *
+ *   make dist STORES_API=https://staging.example.org/api/stores
+ *
+ * Read from the package.json that ships inside the app, so a packaged build answers with
+ * what it was built with. A runtime `STORES_API` still wins over it — that is for trying
+ * something out, this is for shipping it.
+ */
+export class BuildConfiguration {
+  private cached: Readonly<Record<string, unknown>> | null = null
+
+  public readRegistryUrl (): string | null {
+    const section = readRecord(this.read(), 'warpEngine')
+    if (section === null) return null
+    const url = readString(section, 'registryUrl').trim()
+    return url.length > 0 ? url : null
+  }
+
+  private read (): Readonly<Record<string, unknown>> {
+    if (this.cached !== null) return this.cached
+    // build/infrastructure/config → the package root, packaged or not.
+    const candidates = [
+      path.join(__dirname, '..', '..', '..', 'package.json'),
+      path.join(__dirname, '..', '..', 'package.json')
+    ]
+    for (const candidate of candidates) {
+      try {
+        const parsed = asRecord(JSON.parse(fs.readFileSync(candidate, 'utf8')))
+        if (parsed !== null) {
+          this.cached = parsed
+          return parsed
+        }
+      } catch {
+        // Try the next one; a missing package.json is only fatal if none is found.
+      }
+    }
+    this.cached = {}
+    return this.cached
+  }
+}
diff --git a/src/infrastructure/mappers/EngineGameMapper.ts b/src/infrastructure/mappers/EngineGameMapper.ts
index 281976f..9c25bc2 100644
--- a/src/infrastructure/mappers/EngineGameMapper.ts
+++ b/src/infrastructure/mappers/EngineGameMapper.ts
@@ -1,4 +1,4 @@
-import type { Game, GameMode } from '../../domain/models/Game'
+import type { Game, GameMode, UnavailableReason } from '../../domain/models/Game'
 import {
   readBoolean, readOptionalString, readString, type JsonRecord
 } from '../json/JsonRecord'
@@ -26,11 +26,27 @@ export class EngineGameMapper {
       installedVersion: readOptionalString(record, 'installed_version'),
       menuEntryPath: readOptionalString(record, 'menu_entry'),
       executablePath: readOptionalString(record, 'exe'),
-      hostedUrl: readOptionalString(record, 'url')
+      hostedUrl: readOptionalString(record, 'url'),
+      // Absent means installable: engines older than 1.2.0 list only what they can
+      // install, and treating their silence as "unavailable" would empty the window.
+      installable: readBoolean(record, 'installable', true),
+      unavailableReason: this.toReason(readOptionalString(record, 'unavailable_reason')),
+      unavailableDetail: readOptionalString(record, 'unavailable_detail')
     }
   }
 
   private toMode (value: string): GameMode {
     return value === 'web' ? 'web' : 'app'
   }
+
+  /** The engine's snake_case codes, which are its wire format and not ours. */
+  private toReason (value: string | null): UnavailableReason | null {
+    const codes: Readonly<Record<string, UnavailableReason>> = {
+      platform_off: 'platformOff',
+      host_asset: 'hostAsset',
+      no_asset: 'noAsset',
+      vetoed: 'vetoed'
+    }
+    return value === null ? null : codes[value] ?? null
+  }
 }
diff --git a/src/infrastructure/repositories/HttpStoreRegistryRepository.ts b/src/infrastructure/repositories/HttpStoreRegistryRepository.ts
index 9c3cb52..f6b653d 100644
--- a/src/infrastructure/repositories/HttpStoreRegistryRepository.ts
+++ b/src/infrastructure/repositories/HttpStoreRegistryRepository.ts
@@ -2,6 +2,7 @@ import { RegistryUnavailableError } from '../../domain/errors/RegistryUnavailabl
 import type { RegistryStore } from '../../domain/models/RegistryStore'
 import type { StoreRegistryRepository } from '../../domain/ports/StoreRegistryRepository'
 import { asRecord, readString, type JsonRecord } from '../json/JsonRecord'
+import { BuildConfiguration } from '../config/BuildConfiguration'
 import type { HttpTextClient } from '../http/HttpTextClient'
 
 const DEFAULT_REGISTRY_URL = 'https://teletypegames.org/api/stores'
@@ -9,8 +10,10 @@ const DEFAULT_REGISTRY_URL = 'https://teletypegames.org/api/stores'
 /**
  * The registry: `GET /api/stores` on the site.
  *
- * The one address this client knows, and even that is overridable — `STORES_API`
- * points it at another site or at a local endpoint.
+ * The one address this client knows, and it is decided in three places, most specific
+ * first: a runtime `STORES_API` (for trying something out), the `warpEngine.registryUrl`
+ * field a build was packaged with (for shipping a client for another site), and finally
+ * the address of ours.
  *
  * A record needs a name and a catalog URL; those two make a store. The repository
  * is optional and arrives as null when absent — a store configured by nothing but
@@ -20,11 +23,16 @@ const DEFAULT_REGISTRY_URL = 'https://teletypegames.org/api/stores'
 export class HttpStoreRegistryRepository implements StoreRegistryRepository {
   public readonly sourceUrl: string
 
-  public constructor (private readonly httpClient: HttpTextClient, sourceUrl?: string) {
-    const configured = process.env['STORES_API']
-    this.sourceUrl = sourceUrl ?? (configured !== undefined && configured.length > 0
-      ? configured
-      : DEFAULT_REGISTRY_URL)
+  public constructor (
+    private readonly httpClient: HttpTextClient,
+    sourceUrl?: string,
+    buildConfiguration: BuildConfiguration = new BuildConfiguration()
+  ) {
+    const fromEnvironment = process.env['STORES_API']
+    this.sourceUrl = sourceUrl
+      ?? (fromEnvironment !== undefined && fromEnvironment.length > 0 ? fromEnvironment : null)
+      ?? buildConfiguration.readRegistryUrl()
+      ?? DEFAULT_REGISTRY_URL
   }
 
   public async listStores (): Promise<readonly RegistryStore[]> {
diff --git a/src/main/ElectronApplication.ts b/src/main/ElectronApplication.ts
index 9a69c21..7b5b1c7 100644
--- a/src/main/ElectronApplication.ts
+++ b/src/main/ElectronApplication.ts
@@ -6,7 +6,7 @@ import { SelfTestRunner } from './diagnostics/SelfTestRunner'
 
 const SELFTEST_FLAG = '--selftest'
 const SELFTEST_USER_DATA_DIRECTORY = 'warpstore-gui-selftest'
-const PRODUCT_NAME = 'WarpEngine Store'
+const PRODUCT_NAME = 'WarpEngine Client'
 
 /**
  * The application's lifecycle.
diff --git a/src/main/MainWindowFactory.ts b/src/main/MainWindowFactory.ts
index 8280bed..904d40c 100644
--- a/src/main/MainWindowFactory.ts
+++ b/src/main/MainWindowFactory.ts
@@ -7,7 +7,7 @@ const WINDOW_OPTIONS: BrowserWindowConstructorOptions = {
   minWidth: 760,
   minHeight: 520,
   backgroundColor: '#11151c',
-  title: 'WarpEngine Store'
+  title: 'WarpEngine Client'
 }
 
 /**
diff --git a/src/renderer/index.html b/src/renderer/index.html
index acf0f7d..22bf5ed 100644
--- a/src/renderer/index.html
+++ b/src/renderer/index.html
@@ -6,7 +6,7 @@
        runs: the app ships its own script and stylesheet. -->
   <meta http-equiv="Content-Security-Policy"
         content="default-src 'none'; script-src 'self'; style-src 'self'; img-src 'self' https: data:; font-src 'self'; connect-src 'none'">
-  <title>WarpEngine Store</title>
+  <title>WarpEngine Client</title>
   <link rel="stylesheet" href="style.css">
 </head>
 <body>
@@ -16,8 +16,10 @@
     </button>
     <div class="bar-title">
       <span class="logo" aria-hidden="true">▚</span>
-      <span id="app-name">WarpEngine Store</span>
-      <span class="store-id" id="store-id"></span>
+      <span id="app-name">WarpEngine Client</span>
+      <!-- Kept for the window check, which reads it to see which store is open; the
+           side menu is where a person reads that. -->
+      <span class="store-id" id="store-id" hidden></span>
     </div>
     <div class="bar-actions">
       <span class="progress" id="progress" hidden></span>
diff --git a/src/renderer/state/CategoryFilter.ts b/src/renderer/state/CategoryFilter.ts
index 39c9178..3a23b7d 100644
--- a/src/renderer/state/CategoryFilter.ts
+++ b/src/renderer/state/CategoryFilter.ts
@@ -30,7 +30,9 @@ export function matchesFilter (game: GameDto, filter: CategoryFilter): boolean {
     case 'platform':
       return game.platform === filter.value
     case 'mode':
-      return game.mode === filter.value
+      // A title this machine cannot install has no mode worth filtering on: the engine
+      // sends none, and counting it as native would put a C64 cartridge under "native".
+      return game.installable && game.mode === filter.value
     case 'group':
       return matchesGroup(game, filter.value)
   }
@@ -43,7 +45,9 @@ function matchesGroup (game: GameDto, group: string): boolean {
     case 'updates':
       return game.updateAvailable
     case 'available':
-      return !game.installed
+      return game.installable && !game.installed
+    case 'unsupported':
+      return !game.installable
     default:
       return true
   }
@@ -68,7 +72,8 @@ export function buildCategorySections (
     { kind: 'group', value: 'all', label: messages.catAll, count: games.length },
     { kind: 'group', value: 'installed', label: messages.catInstalled, count: count((game: GameDto): boolean => game.installed) },
     { kind: 'group', value: 'updates', label: messages.catUpdates, count: count((game: GameDto): boolean => game.updateAvailable) },
-    { kind: 'group', value: 'available', label: messages.catAvailable, count: count((game: GameDto): boolean => !game.installed) }
+    { kind: 'group', value: 'available', label: messages.catAvailable, count: count((game: GameDto): boolean => game.installable && !game.installed) },
+    { kind: 'group', value: 'unsupported', label: messages.catUnsupported, count: count((game: GameDto): boolean => !game.installable) }
   ]
   sections.push({
     title: null,
@@ -90,7 +95,8 @@ export function buildCategorySections (
     })
   }
 
-  const modes = [...new Set(games.map((game: GameDto): string => game.mode))]
+  const installable = games.filter((game: GameDto): boolean => game.installable)
+  const modes = [...new Set(installable.map((game: GameDto): string => game.mode))]
   if (modes.length > 1) {
     sections.push({
       title: messages.catMode,
@@ -98,7 +104,7 @@ export function buildCategorySections (
         kind: 'mode',
         value: mode,
         label: mode === 'web' ? messages.hosted : messages.native,
-        count: count((game: GameDto): boolean => game.mode === mode)
+        count: count((game: GameDto): boolean => game.installable && game.mode === mode)
       }))
     })
   }
diff --git a/src/renderer/style.css b/src/renderer/style.css
index b22c8d4..ea120bc 100644
--- a/src/renderer/style.css
+++ b/src/renderer/style.css
@@ -14,6 +14,22 @@
 
 * { box-sizing: border-box; }
 
+/* The scrollbars are part of the theme too: the platform's own are light, and a white
+   track down the side menu of a dark window looks like a mistake. */
+* {
+  scrollbar-width: thin;
+  scrollbar-color: #33414f transparent;
+}
+::-webkit-scrollbar { width: 10px; height: 10px; }
+::-webkit-scrollbar-track { background: transparent; }
+::-webkit-scrollbar-thumb {
+  background: #33414f;
+  border: 3px solid transparent;
+  border-radius: 999px;
+  background-clip: content-box;
+}
+::-webkit-scrollbar-thumb:hover { background: #46586b; background-clip: content-box; }
+
 /* An explicit `display` beats the browser's own [hidden] rule, and most of the
    regions here have one — the gate's store picker showed as an empty stub because
    of exactly that. This makes `hidden` mean hidden everywhere. */
@@ -248,6 +264,12 @@ body.nav-closed .side { margin-left: calc(-1 * var(--side-width)); }
   flex-direction: column;
 }
 .card.is-installed { border-color: #2f5a49; }
+/* Listed, but not for this machine: dimmed rather than hidden, and it says why. */
+.card.is-unavailable { opacity: .55; }
+.card.is-unavailable:hover { opacity: .8; }
+.card.is-unavailable .art { filter: grayscale(1); }
+.badge-unavailable { color: var(--ink-dim); border-color: var(--line); border-style: dashed; }
+.actions-note { font-size: 12px; color: var(--ink-dim); margin-top: auto; }
 
 .art {
   /* One height for every card, art or not, so the titles and the buttons line up
diff --git a/src/renderer/views/GameCardView.ts b/src/renderer/views/GameCardView.ts
index e5ccd33..1b58f54 100644
--- a/src/renderer/views/GameCardView.ts
+++ b/src/renderer/views/GameCardView.ts
@@ -20,6 +20,7 @@ export class GameCardView {
   public createCard (game: GameDto, messages: MessageBundle, busy: boolean): HTMLElement {
     const card = createElement('article', 'card')
     if (game.installed) card.classList.add('is-installed')
+    if (!game.installable) card.classList.add('is-unavailable')
     card.appendChild(this.createArt(game))
     card.appendChild(this.createBody(game, messages, busy))
     return card
@@ -54,10 +55,21 @@ export class GameCardView {
 
   private createMeta (game: GameDto, messages: MessageBundle): HTMLElement {
     const meta = createElement('div', 'meta')
-    const mode = createElement('span', `badge badge-${game.mode}`,
-      game.mode === 'web' ? messages.hosted : messages.native)
-    mode.title = game.mode === 'web' ? messages.hostedHint : messages.nativeHint
-    meta.appendChild(mode)
+    if (game.installable) {
+      const mode = createElement('span', `badge badge-${game.mode}`,
+        game.mode === 'web' ? messages.hosted : messages.native)
+      mode.title = game.mode === 'web' ? messages.hostedHint : messages.nativeHint
+      meta.appendChild(mode)
+    } else {
+      // Which of the two it is matters: a platform this store does not carry is a
+      // different disappointment from a game with no build for your machine.
+      const label = game.unavailableReason === 'platformOff'
+        ? messages.unsupportedPlatform
+        : messages.unsupportedBuild
+      const badge = createElement('span', 'badge badge-unavailable', label)
+      badge.title = game.unavailableDetail ?? label
+      meta.appendChild(badge)
+    }
     meta.appendChild(createElement('span', 'badge badge-plain', game.platform))
     meta.appendChild(createElement('span', 'version',
       game.installed && game.installedVersion !== null
@@ -68,6 +80,15 @@ export class GameCardView {
 
   private createActions (game: GameDto, messages: MessageBundle, busy: boolean): HTMLElement {
     const actions = createElement('div', 'actions')
+
+    // Nothing to offer, so nothing to press: a disabled Install would invite a click
+    // that can never work. The badge above says why.
+    if (!game.installable) {
+      actions.appendChild(createElement('span', 'actions-note',
+        game.unavailableDetail ?? messages.unsupportedPlatform))
+      return actions
+    }
+
     const primary = createElement('button', 'btn btn-primary')
     primary.disabled = busy
 
diff --git a/src/renderer/views/TopBarView.ts b/src/renderer/views/TopBarView.ts
index fef23e7..839023b 100644
--- a/src/renderer/views/TopBarView.ts
+++ b/src/renderer/views/TopBarView.ts
@@ -18,8 +18,9 @@ export class TopBarView {
 
   public render (state: AppState): void {
     setText(this.appName, state.messages.appName)
-    // The badge is a bordered pill: empty, it renders as a stub next to the title.
-    setHidden(this.storeId, state.currentStore === null)
+    // The bar names the app, not the store: which store is open is what the switcher in
+    // the side menu says, and saying it twice made the title read like a breadcrumb. The
+    // element stays in the page, hidden, because the window check reads it.
     setText(this.storeId, state.currentStore === null ? '' : state.currentStore.id)
     this.navToggle.title = state.messages.menu
     this.navToggle.setAttribute('aria-label', state.messages.menu)
diff --git a/src/scripts/SmokeTest.ts b/src/scripts/SmokeTest.ts
index 29fbe57..8919b49 100644
--- a/src/scripts/SmokeTest.ts
+++ b/src/scripts/SmokeTest.ts
@@ -167,9 +167,22 @@ class SmokeTest {
   }
 
   private reportListing (games: readonly GameDto[]): void {
-    const native = games.filter((game: GameDto): boolean => game.mode === 'app').length
-    const hosted = games.length - native
-    this.reportOk('list', `${String(games.length)} titles (app:${String(native)}, web:${String(hosted)})`)
+    const installable = games.filter((game: GameDto): boolean => game.installable)
+    const native = installable.filter((game: GameDto): boolean => game.mode === 'app').length
+    const hosted = installable.length - native
+    this.reportOk('list', `${String(games.length)} titles ` +
+      `(app:${String(native)}, web:${String(hosted)}, unavailable:${String(games.length - installable.length)})`)
+
+    // The listing is supposed to carry what it cannot install, with a reason on each.
+    const unavailable = games.filter((game: GameDto): boolean => !game.installable)
+    const unexplained = unavailable.filter((game: GameDto): boolean => game.unavailableReason === null)
+    if (unexplained.length > 0) this.reportBad('unavailable', `${String(unexplained.length)} have no reason`)
+    else if (unavailable.length > 0) {
+      const first = unavailable[0]
+      if (first !== undefined) {
+        this.reportOk('unavailable', `${String(unavailable.length)}, e.g. ${first.name}: ${first.unavailableReason ?? ''}`)
+      }
+    }
 
     const withoutTitle = games.filter((game: GameDto): boolean =>
       game.name.length === 0 || game.title.length === 0 || game.platform.length === 0)
diff --git a/src/shared/contracts/dto/GameDto.ts b/src/shared/contracts/dto/GameDto.ts
index 5465318..b762700 100644
--- a/src/shared/contracts/dto/GameDto.ts
+++ b/src/shared/contracts/dto/GameDto.ts
@@ -1,6 +1,9 @@
 /** How a title runs: unpacked on this machine, or served as a web build. */
 export type GameModeDto = 'app' | 'web'
 
+/** Why a title cannot be installed on this machine. */
+export type UnavailableReasonDto = 'platformOff' | 'hostAsset' | 'noAsset' | 'vetoed'
+
 /**
  * A catalog entry as the window needs it.
  *
@@ -23,4 +26,8 @@ export interface GameDto {
   readonly updateAvailable: boolean
   readonly installedVersion: string | null
   readonly launchable: boolean
+  /** False for a title this machine cannot install; it is listed all the same. */
+  readonly installable: boolean
+  readonly unavailableReason: UnavailableReasonDto | null
+  readonly unavailableDetail: string | null
 }
diff --git a/src/shared/i18n/EnglishMessages.ts b/src/shared/i18n/EnglishMessages.ts
index d1bb43d..30851c2 100644
--- a/src/shared/i18n/EnglishMessages.ts
+++ b/src/shared/i18n/EnglishMessages.ts
@@ -5,7 +5,7 @@
  * translation is a compile error rather than a blank label at runtime.
  */
 export const ENGLISH_MESSAGES = {
-  appName: 'WarpEngine Store',
+  appName: 'WarpEngine Client',
   refresh: 'Refresh',
   install: 'Install',
   update: 'Update',
@@ -18,6 +18,8 @@ export const ENGLISH_MESSAGES = {
   hostedHint: 'Opens in your browser — needs the network',
   nativeHint: 'Installed on this machine — works offline',
   updateAvailable: 'update available',
+  unsupportedPlatform: 'unsupported platform',
+  unsupportedBuild: 'no build for this machine',
   log: 'Log',
   menu: 'Menu',
   stores: 'Stores',
@@ -29,6 +31,7 @@ export const ENGLISH_MESSAGES = {
   catInstalled: 'Installed',
   catUpdates: 'Updates',
   catAvailable: 'Not installed',
+  catUnsupported: 'Not for this machine',
   catPlatform: 'Platform',
   catMode: 'Kind',
   language: 'Language',
diff --git a/src/shared/i18n/HungarianMessages.ts b/src/shared/i18n/HungarianMessages.ts
index 08d9cce..69d9dff 100644
--- a/src/shared/i18n/HungarianMessages.ts
+++ b/src/shared/i18n/HungarianMessages.ts
@@ -5,7 +5,7 @@ import type { MessageBundle } from './MessageBundle'
  * arrives from the store as it was published.
  */
 export const HUNGARIAN_MESSAGES: MessageBundle = {
-  appName: 'WarpEngine Store',
+  appName: 'WarpEngine Client',
   refresh: 'Frissítés',
   install: 'Telepítés',
   update: 'Frissítés',
@@ -18,6 +18,8 @@ export const HUNGARIAN_MESSAGES: MessageBundle = {
   hostedHint: 'A böngészőben nyílik meg — internet kell hozzá',
   nativeHint: 'Erre a gépre telepítve — internet nélkül is megy',
   updateAvailable: 'frissítés elérhető',
+  unsupportedPlatform: 'nem támogatott platform',
+  unsupportedBuild: 'ehhez a géphez nincs build',
   log: 'Napló',
   menu: 'Menü',
   stores: 'Store-ok',
@@ -29,6 +31,7 @@ export const HUNGARIAN_MESSAGES: MessageBundle = {
   catInstalled: 'Telepítve',
   catUpdates: 'Frissítés',
   catAvailable: 'Nincs telepítve',
+  catUnsupported: 'Erre a gépre nem',
   catPlatform: 'Platform',
   catMode: 'Fajta',
   language: 'Nyelv',