I cannot manage to get a new user created whether i use the "login with facebook" button on the wp admin page or by using the "register with facebook" button on the buddypress register page. I always end up being logged in with the admin account i use for managing the site, and no new account is created. New account creation works fine when i use other plugins however, for example with WP-Facebook Autoconnect.
I also noticed that my BbPress forum becomes invisible whenever the Ultimate Facebook plugin is activated. The forum is here, the urls work but most of the content is simply not displayed on the page.
On a sidenote, is it necessary to use the facebook registration form on the register page? Why not simply let people log in using facebook and create a wordpress account using their facebook info?