Sorry for the inconvenience but if I proposed to try to port DarkRadiant on XP it's just that I do not have the money (one to two years) to buy a descent computer (and a good graphics card ) that can support Windows 8 or more. During this period I will use version 1.8 (or maybe use NetRadiant or GTKRadiant). It's not my fault if Microsoft does not want to support Windows XP (in some years, Windows Vista, Windows 7 and Windows 8 will in turn be obsolete and the problem will be new recurring). I personally use GCC (mingw or mingw64) to compile a personal Doom3 engine which allows me to use it for various Windows XP and newer version (friends).