in your link you have Joomla core with Easy Profile Fields registration (this is correct), but the problem is due to K2 user registration, try to disable this from Administration->Components->K2->Options->Advanced->Enable K2 User Profile
Hey there,
Just add a menu item to the joomla user registration. It should be as easy as that. This tool, adds to the core joomla user profile, it does not replace it.
Hope this helps,
-Victor