I'm happy to say ( so far ) , that my bookmarking problems seem to have gone away.
I've stopped using them ...
All I've done is take the SD card that I received from Bookeen , re-formatted it at FAT32 ( instead of FAT as was ) . For at least 3 weeks I've been blessed with my Cybook remembering each last page read , with 3 different books currently on the go .
I've not used mobipocket reader in an awfully long time , I've stored my e-books in a totally different folder on my computer , and download all my e-books directly to that .
Needless to say I always use " remove hardware safely " .