I've never programmed in the windows environment myself , but at a gues the API's for win98 and win2k are very similar , at least on the library level what the library does after receiving say a sound routine call on those os'es is a different story.BUT win2k is a whole different beast underneath the 'engine' that makes it much more stable with programs running on it as well as programs running for it. Memory management & process management are different than win win98. So I dont think the Winuae e guys can actually do much with it ,like your suggesting spliting the code. If the Direct X api is set in stone for all windows platforms it should do what the programmer expects it to do and leave all the other stuff (i.e screen rez) to the display drivers et al.
dunno maybe all the above is bull...:0