1 WordPress Installation Multiple phpBB Forums

We are evaluating a few CMS options and I was hoping to get some help on validating if WordPress can achieve what we are looking for. We are looking to have the following functionality:

1. One WordPress instillation that links to several phpBB forums. So when a user registers at the main WordPress website, they have instant access to all phpBB installations.

a. I have seen a few plugins and the ratings all over the board. I am also not sure if one of them can handle this scenario.
b. I also want to make sure when we add new phpBB forums, all of the main websites resisted users have instant access to the new forum.

2. We would also like any user that signs up for a class to have access to a special locked section of the related phpBB forum.

a. I know this can be completed manually, but we are hoping if we can assign a user to a permissions group after they sign up for a class, that permissions will update in phpBB. Allowing that user to have instant access to a few locked threads in the related phpBB forum.

Any assistance or suggestions would be greatly appreciated.