I was able to login using Facebook on these support pages so that's a bit odd. Anyway, am letting you know because your product is about Facebook integration and it doesn't look good that it doesn't work on your own site.
Peter,
Thanks for the report. The issue was a temporary glitch with Facebook itself and their Javascript library. We were investigating the issue when it was fixed. Feel free to try again, and if run into issues, please do let us know!