Help With PayPal Express - with Single Payments [Sooo Frustrating]

Hi Guys,
Please help, I have created a register page here
That you can get to from the home page, I got a friend to test it out and the paypal payment
goes through fine but when I check in 'membership > all members' It shows him as 'inactive'

And he gets redirected to the site home page instead of giving him access to the members area.

Thanks so much in advance, really appreciate any advice you can give me please.