Facebook Comments not working

I just tried to install JFBConnect and use the SCSocialWidget to add a FacebookComment area to a site.
I've got the module displaying, but all I get is what looks to be a facebook button saying:
"Log in to Facebook to Post a Comment"
I'm already logged in to FB in a different tab.
And clicking that button just returns me to the same page.

I'm getting the same results on another site that had this module installed and working fine up until recently (within the past week or two).

When I check the console upon clicking that button I see the following error (not sure if it has anything to do with it):

Uncaught TypeError: Cannot read property 'LivePass' of undefined
Given URL is not allowed by the Application configuration.: One or more of the given URLs is not allowed by the App's settings. It must match the Website URL or Canvas URL, or the domain must be a subdomain of one of the App's domains.

I'm guessing that either FB changed something on their end, or a recent update of JFB broke something.

Anyone else see this or have any idea what might be causing this?

Here's a link to the original site that WAS working, but now isn't:

vibrantfaithathome.org/item/homesickness-helps-2#.U6ja3vldWSo

(The comments module is in the 'Discuss with others' area)