Can you explain the login event in CB that's being triggered? Is that triggered from a User plugin or somewhere else? What does it do?
JFBConnect uses the standard Joomla login system for Facebook logins. I'm not sure what CB is doing, but if they're expecting all logins to go through their system and not building on top of Joomla's login system, that could be a problem.
As for the redirect itself, I'll let you know what I find in
this thread
that you're also a part of.
Thanks,
Alex