If you're experiencing some issues with Font Awesome, please try the following suggestions:
Turn on "Ligatures" in the character panel. It shouldn't be necessary but we had some reports that this helped.
Remove Font Awesome and install it again. It might have happened that you had a different version of Font Awesome already installed and it causes issues.
On Mac: search for "Font book" in the spotlight and remove the fonts there.
On Windows: check out this guide.