I sent an email to Bookeen too and described the issue in this thread (1st issue) as well as the bookmark issue in a different thread here (2nd issue). Today I received a response from Bookeen:
You describe 2 known issues:
1) The first issue is well identified and an internal software build already solves it. We are finishing its testing before releasing this piece of code in the next software upgrade.
2) The second issue has also been identified. We have made some software modifications which enhance the system behaviour but without completely stabilizing the bookmark feature.
We will release in the next few weeks a software upgrade which fixes at least the first issue. We have no final release date yet, but we work to find a definitive solution to the bookmark issue and integrate it at the same time.