I have a smiliar issue trying to get this to work, get the connection success message then when I press the continue then get an error message.
I saw a thread about changing the wc_facebook_external_business_id in the database, tried this through wp-admin/options.php to no avail so updated the db directly which worked, tried to reconnect, same thing happens I got a success message followed by an error?
Are there any logs created that can be viewed to see where the issue is?
Thanks