You must have Instant Payment Notification (IPN) enabled in your PayPal account for registration records to be created properly. To do this:

(1) Login to your PayPal account and go to Edit Profile.
(2) Under the "Selling Preferences" column, click on "Instant Payment Notification Preferences". The next screen will show if this is On or Off.
(3) To turn in On, click EDIT button.
(4) Then check the checkbox and then input a url in the Notification URL box. If nothing is there, just type in your website URL including the http:// on the front.
(5) Also, in other settings, you must have Auto-return set to OFF.