COT is a great experience. I can address some of your questions...
Last summer (class 04-06), we did not get to shoot, and although everyone wanted to, I don't think they have amended the curriculum. The bright side of that is, you will get to go home a few days early while your JAG buddies stick around in boring Alabama.
You will get to participate in various classroom, field training, and pt exercises. A typical day consists of you waking up at 0430, pt at 0500, classroom and field activities from 0700-1730, and then the rest of the time to take care of things like homework, uniform issues, etc. After the first week, you are granted liberty leave base any day after the training day is over. Weekends are free.
The PT is easy to handle if you are in good shape, but the summer weather in Alabama is very hot and humid, so keep hydrated. The most we ran was 3 miles with the BOT students one day. Most of us did extra PT on the weekends and such
You don't know your flight assignments until the first day (TD 0). Unfortunately, you will not socialize much outside your flight.
Noone really fails COT. Some people dropped out due to medical or other reasons, but that was like 10 people in a 300 person class. The only way you can be considered 'incomplete' is if you fail the examinations (CWTs they are called. If you fail the first two they make you take a composite. Usually not a concern for medical officers, but if you do fail, even then they dont make you repeat it, it just goes on your record.
Arrive motivated, stay positive, and follow the lead of the prior service attendees since they will keep you out of trouble. It goes by very fast (maybe a little too fast if you're having fun).
-Lt.