I have consistently encountered issues with my Map/Background images as well as some of my tokens disappearing on my maps. All of the images tied to these backgrounds and tokens that have gone missing are sitting in my upload library, so from the other forum topics I've seen posted regarding issues like this, I can't imagine it would have anything to do with the images being gone. The tokens that I place have GM Notes and information tied to them, and consistently having to re-place these tokens and re-add the information has become tiresome.