Okay so we know the update fixed the sideloaded TOC issue.
Obviously there is a new guideline for sideloaded books and pdocs covers. They need to be HUGE! As Becky posted 1066x1600 works perfectly on both Sideloaded and..... Personal Documents covers! No more generic covers on the carousel!
Let's say Hurray for Becky!!!
This is going to be alot of work for me but so far I had only 34 books converted for the Kindle Fire so that's not too bad of a number to redo right now I've done 6.