fixes:

- make prefix imported games paths relative to prefix
- show placeholder icon as fallback
- fix crossed working/exe directories
- fix broken working dir in prefix imported games

src/ipc/index.js

@@ -93,6 +93,8 @@ function registerIpc({ getWindow, onGamesChanged }) {
   // games: library -----------------------------------------------------------------
   ipcMain.handle('games:list', () => library.loadGames())
   ipcMain.handle('games:get', (e, id) => library.getGame(id))
+  // prefix pin is enforced inside library.updateGame (prefix/importSource
+  // fields are ignored for prefix imports), so nothing extra needed here
   ipcMain.handle('games:update', (e, id, patch) => library.updateGame(id, patch))
   ipcMain.handle('games:remove', (e, id) => {
     shortcuts.removeShortcut(id)
@@ -204,7 +206,15 @@ function registerIpc({ getWindow, onGamesChanged }) {
 
   // dialogs & shell ---------------------------------------------------------------------------
   ipcMain.handle('dialog:pickFile', async (e, opts) => {
-    const res = await dialog.showOpenDialog(getWindow(), { properties: ['openFile', 'openDirectory'], ...(opts || {}) })
+    const o = { ...(opts || {}) }
+    // Electron resolves a RELATIVE defaultPath against the process cwd (the
+    // install root in packaged mode), which lands the picker somewhere
+    // random like '/'. Renderer paths are FILES-relative by convention, so
+    // anchor them there instead.
+    if (o.defaultPath && typeof o.defaultPath === 'string' && !path.isAbsolute(o.defaultPath)) {
+      o.defaultPath = path.join(DIRS.FILES, o.defaultPath)
+    }
+    const res = await dialog.showOpenDialog(getWindow(), { properties: ['openFile', 'openDirectory'], ...o })
     return res.canceled || !res.filePaths[0] ? null : res.filePaths[0]
   })
   ipcMain.handle('shell:openPath', (e, p) => shell.openPath(p))