I did eject the drive, and I dragged the update into the top-level folder. It seems that other people are having similar problems. Some people got the documents back by deleting them and sideloading again, 15-20 at a time, to find out what documen was causing the problems. (It seems that all it takes is one file that worked in version 1.3 but doesn't work in 1.4.) Others got the documents back by restarting several times.
I used tis as a chance to reorganize my ebooks on the book as too many got the author listing wrong. (An author name that is followed by "et al" should not be sorted by last nme "al."
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