I am interested in integrating aMember with an existing Xenforo forum. We would like to retain signup with the Xenforo site. When someone wants to upgrade, can we simply pass the userid or username to aMember and then aMember will add a secondary usergroup upon payment completion? Then, when the paid subscription ends, or user cancels, or payment is declined, etc., then aMember removes the secondary usergroup in Xenforo?