I am having trouble granting access to our BuddyPress Groups area to users in our Membership plugin

Buddypress Site: http://gamers3.com
Master site: http://zombieorpheus.com

We have installed the Membership plugin on one of our BuddyPress sites in order to give our kickstarter backers access to exclusive content for behind the scenes content.

Unfortunately, I cannot seem to grant access to /groups on gamers3.com (the BuddyPress groups page). I have managed to grant access to specific groups (http://gamers3.com/groups/hands-of-fate-kickstarter-backers/) but not to the core /groups page.

Do you have any suggestions?

Also, I would like some help in figuring out how to grant access to a particular buddypress group to a particular class of members in the membership plugin.

Do you have any advice for that?