I have had some trouble getting the payment plugin to work correctly. Namely, I can't get users to redirect to a custom url and I've been unable to remove the manual payment entry even when I remove it from the user permissions. Finally, I've tried simply playing around with some PayPal buttons, and I am able to get the registration flow I wanted.
That being said, I was using the Member Payment Plugin because I am trying to make user groups that are contingent on users successfully registering in Tiki. Thus, is there a way to assign users to a specific group upon viewing a specific page?