Very sorry for the delayed response. I'm not sure why the Open Graph integration isn't working properly for you. I'd recommend checking the following items:
* Make sure the page that is being shared is publicly accessible. Facebook needs to scan the page being shared to see the Open Graph tags and if it's for Registered users only, Facebook won't be able to do this.
* Try with SEF URLs turned off in Joomla (or any 3rd party SEF extension you may have enabled)
* Scan the page that's being shared with the
Facebook URL Debug Tool
. That may help uncover if there are any errors on the page with the open graph tags.
Let me know if any of the above helps narrow things down for the first two errors about object references.
An active access token must be used to query information about the current user.
This is an error that can occur after an Open Graph submission fails since it can invalidate the user's authentication token. They will still be logged into your site, but won't be able to post more open graph actions until they've re-authenticated with Facebook.
I hope that helps,
Alex