Hi, JFYI the owners of the code are fairly responsive to licence issues (for instance [1]) and tend to give permission to use their stuff (few other issues). I think the simplest way to resolve this may be ask can we use the font files under an more permissive / Apache compatible licence. We should also make clear we are redistributing those files as well when asking.
Files in question are probably flat-ui-icons-regular.eot, flat-ui-icons-regular.swf, flat-ui-icons-regular.ttf, flat-ui-icons-regular.woff and lat-ui-icons-regular.svg. (I looked inside the ttf one and it also states it has a non commercial license). Thanks, Justin 1. https://github.com/designmodo/Flat-UI/issues/18