After my lack of success with the Bookeen store I took a deep breath and bought a couple of titles this morning from both Fictionwise and BooksOnBoard.
What a difference. Fictionwise was plain sailing. I had a small problem with BooksOnBoard (of my own making as it turned out, I simply hadn't given them time following my payment to activate my download links) and following my email I had an instant - and helpful - automated response and a personal response shortly after.
I know who I'll be buying my books from in future.

Yes, FictionWise are definitely "good guys".

What I'd suggest as far as the issue with Bookeen's store is concerned is that you send them an email saying "if you don't resolve my problem by Monday" (or whatever you think is reasonable) "I'll contact my credit card company and request a charge-back".

Yes, I think I'll do that if I haven't heard anything from them. It's a pity, I would have liked to support them.
Possibly they can't compete with the prices of the other online book stores, and with a smaller customer base they can't adequately staff their own, but failing to 'deliver the goods' and failing to respond to customers' emails will never help them to grow.
Still, I love my Cybook Gen 3.