I firmly believed there was a bug with CB 1.1 and Mambo 4.6.2 Mambo was refusing to show me the users in the userlist ...
It turned out that when I deinstalled the CB1.1RC versions and reinstalled the Final release, the Db tables aren't deleted, and obviously that was the problem, because when I manually deleted them, and thus did a "clean" reinstall of CB 1.1 final release, it worked. Me happy!