Thanks for the advice. I was a little panicky--I had been so looking forward to getting the Cybook and was so sad that it didn't seem to be working!
I still have to go through and sort out what I want and what I don't want, as I have tons of e-books, and oddly some of my eReader books copied over as Mobipocket (they're Fictionwise multi-format books). But I've got lots of books loaded now--enough to keep me reading for years! Feedbooks and manybooks.net both rock my socks.