I see that gradebook2 is updated in contrib, however the course/lib file is dated 8/26, as are the quiz/lib and assignment/lib & submissions files. So I take there is no fix yet for the issues I ran into previously.
Did you have a chance to look at my other questions? Basically we're trying to figure out what part of the way its working is a feature and which is a bug? Eg do you intend to have grades entered for the moodle modules in the gradebook only, or should the modules be able to send their grades to the gradbook?
Some kind of roadmap/requirements doc./planned feature set would be helpful before we start working on this, we don't want to 'fix' things that you see as features.