How to use the Rules module to award userpoints to referring users? I am creating a referral program on Drupal. I have almost everything working right except awarding userpoints to users. I want to award userpoints to users after the person they refer to the site becomes a paid member. I have tried severally with Rules but no success.

I am using these modules:


User Referral module to capture referrals.
User Points to award userpoints.
Membership Entity to create paid members.


What I want is to create a rule using Rules that automatically awards userpoints to a user once the person that a user refers to the site becomes a paid member of the site.

Anyone with better knowledge able to help me out here?
Add a field to user registration form that collects the uid of the referring user. Then ask current users to invite other people to the site using a custom URL to user registration form and this URL should include as query parameter the uid of the referring user. Hook the user registration form and fill in the uid of the referrer based on the query parameter. You should hide the referrer field completely. Then you do counts in the database for how many paid users a given uid had invited. The referrer uid in regard to each user is kept in the custom user profile field and becomes meaningful in your situation if the user becomes a paid member.