When I try to download a file, of say 500K, I only get about 50% of it, and, of course, Books won't open it. If I choose TEXT, I get the whole file and can read it off-line, but lose all the benefits of the app Books.
I have been using SOL for, I think, twenty years and this is only the second glitch I've encountered.
I tried increasing the available storage and cold starting my iPad without success.