How do I fix Login With Facebook on Comments+ please?

Hi there.

I run YorkMix – http://www.yorkmix.com/. We have Comments+ installed, so people can comment directly on the site through Facebook, and Ultimate Facebook, so comments left on FB are pulled into our comments section.

It used to work wonderfully.

We have just updated our theme. Ultimate Facebook still appears to be working fine at pulling in FB comments.

But if you are logged out of Facebook and click on the "Login with Facebook" next to the comments at the bottom of any post it takes you nowhere.

Sometimes if you are logged in to Facebook it doesn't register this either.

I've tried…

– deactivating other plugins
– creating a new Facebook Application for Comments+
– changing the configurations of both Comments+ and Ultimate Facebook and updating, emptying the caches as I went
– running the troubleshooter on Comments+ which gave this error message: "Checking Facebook initialization: failure"

Could you help me get it working again please?

Best wishes,

Chris