Gallery2 + PHPNuke paid() function

I have a site that uses the PHPNuke paid() function, which returns true/false for phpnuke subscribers.

Can I access this function from within an embedded gallery?

Or more specifially, can i allow access to something based on this flag?
I'm quite happy to modify the module itself .. I just don't know how to use paid() from within an .inc file.

Or, does a subscribed member map to a group automatically in the embedded gallery? I've only got "Registered", "Everyone" & "Admin" as groups ..

Thanks in advance for any help!