Wordpress bug fix with S2Member plugin

We have a wordpress website that is up and running and there is a bug with the Membership Plugin [login to view URL] We offer 2 Memberships (same monthly payment fee) : Normal and Professional Both Membership are required to pay 1euro per month as a membership fee. What happens is that when a Professional register and pays with Paypal his account is not created and he doesn't have access to the website. He doesn't receive a Welcome message, he can't login etc. 2 options : Using another membership plugin (other than s2member) OR Fixing the current s2member plugin making sure that the user register FIRST before paying and is properly sent his username and password. Please make sure to bid according to the project scope - GENERIC BIDS WILL BE REJECTED - previous provider wasn't able to solve this problem.