I've setup the latest version of the membership plugin on WP 3.2.1 single site, and configured the plugin according to the "getting started" instructions, to the best of my abilities.
I've just done a test registration. At step one I fill in my details and am emailed the standard WP new account email. At step 2, I select my subscription and pay via PayPal.
When I log in via the link from the standard WP new account email, I'm sent to the Profile on the WordPress dashboard. Have I misconfigured the plugin? I expected that subscribers logging in would be redirected to the main site or to the protected content.