You bet it's windows mobile, mainly because mobipocket didn't reflect the transition to 6.0 at all. And now there is version 6.5.
As for the page turns, well, that's just crappy programming.

But then, it's free, so what am I going on about here.
Gosh, I'm such a grumpy user

. If I was a company I would never sell to myself.
Though you were right that cybook doesn't show these page turning bugs, page turning on cybook is impeccable.