well , judging by the reactos project (which does happend to have a terrible somewhat bloated Gui) , my hint would be to extract the cab and play around with some files and test if it gives good results (the OS seem to be around 40-47 meg installed and most of win programs seem to install on it just fine) borrow some part's here and there and u never know about application patches , besides it's opensource so tweak-it-in the XP-sp2 files would mayhaps prove something? irc.freenode.net seem to have a channel called #reactos , the dev's respond to tech-questions given to them ofcause you have to trigger the part that gets apps working , seems to be less bloated non-ie requirent system DLL's which is good news (but please dont use their active desktop it just stands for trouble )