Thanks for the email. We got interested and decided to look into this sooner
From our testing, there's a very simple solution to your issue. Please edit the /plugins/system/cedit_registrationvalidator.php file. At line 176, you'll see a variable with called $registrationtasks. Simply add the following line to this list of items:
'com_jfbconnect.createnewuser' => 'index.php?option=com_jfbconnect&view=loginregister',
The rest of the code doesn't need to be modified. We setup a simple filter to prevent certain usernames, and the check worked as expected. This should work for any filters you setup, but obviously test.
Please let us know if this works, as we'd love to hear your results. We may try to contact the developers of that plugin cause I can see some benefits of how it could be used with JFBConnect in a few other ways.
Finally, if you'd like to vote or review for JFBConnect on the Joomla Extension Directory, we'd appreciate it.. though of course it's not necessary
extensions.joomla.org/extensions/social-...ook-integration/7215
Thanks, and good luck!