Originally Posted by BobbyRS
Sounds good except for your wallpaper should have been gone after doing a Format or Cleanup.
I'm sorry, but I was wrong. Apparently, when you set a custom wallpaper, this setting seems to be saved somewhere within the firmware on the separate drive partition set aside for the firmware (which doesn't get formatted) instead of on the data partition (basically the same as how the default themes seem to be saved) that actually gets formatted (which erases the users data files). So, it is normal for the ZVM to keep the custom wallpaper even after you do a Format.