Sami B2B Lock,Password Protect

I wanted to like SamiB2B, but unfortunately was told my requirements were "impossible". I wanted to lock a community page, and have access by paying customers - who have a tag on their customer account. I contacted them for support. They only responded when I jumped on chat the next day. They seemed confused when I queried why it was impossible as surely for security, limiting access to specific customers is usual. They responded with the app is "basic". I need better guarantees than this, so looking elsewhere. Disappointing :/