Thank you for sending me your credentials. I fixed the issue. You have the username generation set to be the users Facebook ID only, and unfortunately, in the most recent release of JFBConnect, we apparently broke the {fb_uid} logic.
Ultimately, the fix was to replace ~line 62 with the following:
$username = str_replace("{fb_uid}", $rawFbUserId, $username);
This logic will be deprecated with the newest version. We are moving to a new page which allows the user to set their own username/password/email upon registration. I hope this helps get your site up and running. It's a good looking site, and thank you for letting us get in and perform some tests.
Now to go to some of the other error posts and see if this is their problem.... <!-- s:? --><img src="{SMILIES_PATH}/icon_e_confused.gif" alt="
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