Please make sure you set the Login and Register redirection in both the JFBConnect -> Configuration area and the SCLogin module. They are separate redirects based on how the user is authenticating. The JFBConnect -> Config redirects are used for social network logins. The SCLogin redirects are used for standard Joomla logins.
If that doesn't help, then check the following:
* What happens if you use the Joomla login module?
* Do you have any authentication, user or system plugins that may be trying to redirect the user on authentication?
Let us know how that goes, but if you need any more assistance, just let us know.
Thanks,
Alex