I had this working fine, but recent updates have caused it to stop working correctly ... problem is I can't figure which update caused what.
The instructions for MS install don't work, it throws a file not found which isn't simply fixed by giving the full path ...
Network installing seems to get the comments side working OK, though as wpweaver points out this may be an issue as all can see your secret keys.
But on the registration side you get:-
For security reasons, you must pass the remote ip to reCAPTCHA
And I then noticed that changes to settings are now not saving at all.