it's a 2 stepper --
they would sign up for threads and be put in the 'User' group (as example)
then, they would need to go to 'My Stuff' Subscriptions and signup for the 'Paid group'...
that takes them to Paypal, they fork over the dough and then ubbthreads adds them to the new group..
and ditto the documentation: i have yet to see any documentation on 7.3.1 at all.. i COULD be blind however