I posted this in your ticket on our site, but make sure you're running the correct style version for your forum.
In 2.1 they no longer use a CDN for Font Awesome, they were I believe in 2.0.X. So... with our styles you'll want to run the style version that's related to your forum:
2.0.10 run our 2.0.10 style version.
2.1 run our 2.1 style version ect.
It's loading fine for me now though so not entirely sure if you did fix it or it's still happening for you. If you're still having problems I can take a closer look with an admin login via our support ticket.