I added the fanbox the a new page today and it fails to load anything from Facebook. The module title and "Facebook Fanbox 1.5.x.0" are all I get.
I one point after refreshing the page I got this message:
"Could not retrieve id for the specified page. Please verify correct href was passed in."
This module works great on six or seven other pages but not this one. Nothing special about this page either. It's essentially just a simple article with nothing unique from other pages showing the same Fanbox module.
If I can get this working, I'll be upgrading to pro for sure before the site goes live.