Errors and More Errors

Using ADE to borrow books from the library.  I keep getting errors on a pair of downloads recently added.  I've used this app for a long time and had seen similar issues before, so knew how to troubleshoot from previous experience.  At least, I thought I did. 

No matter how many times I remove (ePub content/the app), reinstall (the app), re-register (the reader), re-download (the ePub content), re-upload (ePub content), it keeps giving me errors and the books keep appearing in the 'on loan' list, even though I have both "Return[ed] Borrowed Item" and "Remove from Library".  On top of that, I can't transfer the books to my eReader.  Help!  this is driving me insane.