Yes, there are some mandatory classes.
All classes have a numeric grade, with the exception of clinical skills, which is P/F.
Depends on the course. When I was in preclinical years, we probably averaged a quiz/exam every 2-3 weeks. I know the new preclinical dean is trying to put all of them on Fridays. Wasn't the case when I was taking them.
Not really, at least in my opinion. They'll tell you they are but they're not really like boards at all speaking from experience. Some are, but a lot aren't. The timing of the exams mirrors boards though in regards to time/question.
Yeah, we had 8 weeks of dedicated. One of the big benefits of WVSOM imo. Plenty of time to teach yourself what you need.