We have just encountered rather weird thing:
1) This first step is probably irrelevant.
We had a 1.9.8 course. It included quizzes with questions populated randomly from Category A.
Question categories were created right in the question bank (not on the quiz level), and the course had a lot of them.
Students took the quiz and got a grade.
This 1.9 course had been copied with user data, and upgraded in-place to 2.0.1+ (Build: 20110217). Everything looks fine in the upgraded course.
2) Then we backed up the 2.0 course and included user data again.
The course was restored to another 2.0 instance.
In that restored course, when we click on "Review attempt" for a student, we see not the questions from Category A that he had answered.
We see questions from some Category B instead.
So it looks like that student was presented with completely different set of questions then he saw in reality.
We restored the course twice - same result: wrong questions from wrong category are shown under Review Attempt.
If I Preview or take the quiz, I see correct questions from Category A.
Any ideas? Anyone encountered similar issue before?
Or may be you have a 2.0 course with random questions to test?
I will try to replicate on a smaller sample.