Hi Gerald,
I'm sorry to hear about your troubles with Activity Tracking in Moodle 2.5.
I can't really offer any help, but I be able to offer some hope when I say that over this past couple of weeks I have completed the scripts to upgrade from QuizPort Moodle 1.9 to TaskChain Moodle 2.x.
I will be working on upgrading the TaskChain grade display script in the near future, so that if you are using TaskChains, you should be able to display the grades on the course page as you were used to doing with QuizPort in Moodle 1.9.
regards
Gordon