Covers and backgrounds
The gallery separates Official, Legacy and My covers or My backgrounds. Select an image to preview it; Apply changes the selection and Apply and close closes the gallery. Double-click or Enter on an item applies it and closes; Esc closes without applying. The action depends on keyboard focus within the gallery.
Import your own image
Use Import image… to choose a test cover or background. The app keeps it in your personal collection, separate from official assets. Avoid personal photos in public screenshots. Missing or invalid images fall back to an official item, according to the inspected controller.
Check persistence
Your cover/background choice is saved locally. Close and reopen the app to check the result in your package. Study backups and personal image backups are separate matters; check both before reinstalling or migrating.