Custom wallpapers should be copied to a local folder in the app directory. Steps to reproduce:
  1. Download any wallpaper to your desktop
  2. Set it as your MASQ background
  3. Exit the app, delete the wallpaper
  4. Load the app again, it's gone and the app looks odd
Would be great if the wallpaper is stored in a locally within the app directory and not from the user's defined location.