When I go to select an icon from the library, the Font Awesome library is the only one that actually shows icons. All other libraries are blank. Then when inserting the icon, it does not show on the page, but an element is created for the icon on the page.
Did you use 3rd plugins that theme does not require? Please deactivate it if you have then check again.
If it still does not work, please provide an admin account so i can help you check.