I don't see any place to enter a Joomla username and password on the page you've provided. The SCLogin setting for login redirection is for logging in only with Joomla credentials, not with the social networks. To set the new user redirection and returning user redirection for social network logins, please update the configuration settings in the JFBConnect > Configuration > General tab.
Let me know if you continue to have issues after setting these two options.
Thanks
-Melissa