John,
Come on, someone here must know! 
such a port is a delicate process, particularly because (as I understand it) the existing code base (for the various editors, not for the compiler) is deeply rooted in some proprietary API which simply doesn't exist on non-Win32 systems. As such, porting the program will almost certainly not be a simple process like searching and replacing certain strings, but involve understanding someone else's source code, understanding the meaning, intent, and interrelationships of the semantics underlying it, mapping those to whichever new API you are using, and re-implementing the code in question (possibly re-using some existing parts). Depending on which APIs are involved, the process _may_ be simpler in some cases, but there is no guarantee that this will be the case.
If you really want to go through with it, your best bet would be to use a well-documented cross-platform API such as one of those listed at
http://www.geocities.com/SiliconValley/Vista/7184/guitool.html.
I would _STRONGLY_ recommend you to try porting one tool at a time, starting with the easiest one(s).
I do not know any of these toolkits, have never touched Win32 programming and have no relevant experience with programming windowing systems, so I don't feel that I could do the "tutoring" part here.
-- Christoph
