How do I get new registrations working using the Membership plugin?

Hi folks,

I'm trying to migrate a forum over to WP from Ning. I've installed the Membership plugin and I can't seem to get it working.

When I register as a new user (http://66.228.55.82) I don't get any confirmation emails. I just get sent back to a page that says "Register" again with the following URI (http://66.228.55.82/register-2/?action=registeruser&subscription=3?login=failed).

Any suggestions on where I'm going wrong?

thanks
Cameron