Missing background as addition to other funny things is, most of the time, mark of filesystem corruption inodes got messed up, and while you've tried to overwrite database files, you actually overwitten other files, that filesystem was pointing to (due to multiply claimed blocks, etc).

Been there, seen that - even more funny things, like some game's save suddenly containing config file of other, unrelated program, etc. If your rtcom-messaging or addresbook tried to load background image as database, no wonder, that you was unable to see any contacts

/Estel