I am having the same problem! It is soooo frustrating!
I am having the same problem, too. Updated edition opens blank. Haven't been able to restore old version. What's going on?
I just finished uninstalling 4.5 and reloaded 4.0 and there was all my books! I had found them on a different spot then I expected on my computer and it would not let me transfer them to 4.5 because "the loan period must be up" although they are MY books! So I said to heck with Adobe Digital, deleted 4.5, found the file for 4.0 on my computer, glad I save everything, and BOW, my books are back! I hope it works for you guys! I am not updating again!