All game assets and demo data (should all be in "Data" folder in the root of the source tree) are not under the same license as the engine code. Wolfire has allowed the _data_ to be _freely_redistributed_ for _non_commercial_purposes_, but it is forbidden to use in any revenue generating works.

http://hg.icculus.org/icculus/lugaru/file/97b303e79826/CONTE...

I find it incredible someone with enough expertise to build the project and get it on the Mac Store can be so clueless with regard to licensing.

Not only are they using unlicensed game assets, but it seems they are violating the GPL as well.

I suspect iCoder knew what it was doing all along.