Compatability btwn S2Member and Groups Plugin

We have a content-heavy subscription website. There are 2000+ pages that are divided among 15 different sections, with the name of the section preceding the name of each page in the URL (e.g. http://domain.com/premium/section-1-name/page-1-name/). Some subscribers want access to all 15 sections. Others are only willing to pay (less) for access to one or two of the sections. This means that there can be many different combinations of sections, with a lot of overlap, among the universe of subscriptions we’d like to offer.

We currently have S2Member on our premium (subscription) site, but the basic Level 1, Level 2, etc. restriction option doesn’t seem to allow us to offer subscriptions in the way we want. I watched the Custom Capabilities videos which seem to suggest we might be able to do what we want, but I’m not sure how to do it. (I’m not very programming literate.)

As an alternative approach, we downloaded the WordPress Groups plugin and set up 15 groups and assigned each of our sections into one of those groups and assigned it a “capability” with a similar name. We then assigned the appropriate “capability” to a few of our website pages in some of the sections. Next, we gave certain test users access to the groups; one had access to a group corresponding to one section, and another user had access to a few groups.

The Groups functionality appears to get overridden by S2Member on our premium site. It seems that S2Member’s Page Level Restriction Access Levels are determining access to pages and ignoring Groups. (As a test, we also loaded the Groups plugin to our free site, which doesn’t use S2Member. Groups worked there just as I hoped it would.)

Is there any way to tweak S2Member or Groups to get the two to work together and do what we want? The only thing I can think of – but don’t know how to do – is to add some kind of URL filter. For example, we might want to give a user access to Section 3. Is there a way to set up a filter that would only allow the user access to pages that have /section-3-name/ in their URL? If I have to add shortcode or otherwise edit all 2000 pages to accomplish that goal, I don’t mind.

Any help would be greatly appreciated.