[www.moddb.com] So this is an open source version of GoldSrc, the Half Life 1 engine. It supports most mods and the SP version of Half Life (CS 1.6 isn't supported) Could this see a Wii port?
The legitimacy of this code seems a bit dodgy, most of it is from Valve with a non-GPL license ("restricted to non-commercial enhancements to products from Valve LLC") mixed with GPL code from other sources which technically isn't allowed.