Ahh.. thanks for reminding us about JMS2WIN. It's very possible there's an issue with his update or some other path issue that's preventing the saving of the avatar. We do handle the avatar and cover a bit differently, simply because CB handles them differently as well.
My best place to start looking is at the temp path we try to save the avatar to when it's downloaded. We use the following code to get the temp directory for your Joomla installation:
$tmpPath = JFactory::getApplication()->getCfg('tmp_path');That normally returns the /tmp directory from your Joomla installation. I don't know where it would be returning on your site and it could be a problem with us saving to one directory and CB trying to read and process it from a different directory. The tmp_path value is set in your configuration.php file and should be the absolute path to your installation. Again though, with JMS2WIN, I don't know how that value should be set correctly.
Either way, JFBConnect tries to save the profile URLs to that directory in a format like scprofile_123_pic_tmp.jpg. I'd look in any directories that could be considered the tmp directory for your site and see if there are files with that format in the directory. If so, then at least you've found where JFBConnect is saving the file and you can check if the avatars work. If so, there's something after the point of downloading that's confusing CB for actually accepting them.
Hopefully that gives you a starting point to investigate some more.
Thanks,
Alex