No, there isn't. Just like Extended Reg has it's own registration form, so does JFBConnect. It, by default, only shows the standard Joomla registration fields, as that's all that's truly required to create a Joomla user. We have a plugin system which other registration systems can add fields to our forms, like Community Builder, JomSocial, Kunena, etc. We don't have a profile plugin for Extended Reg though which can pull the extra fields, display them to the user, and save them back to Extended Reg's table.
Sorry that's not the answer you're looking for. We have documentation on how to create one of our profile plugins, if you have a developer that's interested in looking into it further. Otherwise, I've added it to our list of things to investigate, but I can't give you a timeline as to when that would be implemented.
Thanks,
Alex