Compatibilities

hi,
In fact, i would like to know if there are many modifications to do after applications or games, in order to run under haiku ?
I’m making a rts game, and i’m not using all specific objets like api, windows, … If you prefer, i’m using simple functions, and all the code is lines (my interface is simple lines of code too !). (the system of files, is similary with windows, in fact, letter like c: become in fact a kind of repertory).
Like i see driver, you’re programming alone or you’re making modifications ?

i hope early a release version will come !

Update : Is it possible to keep .bmp .txt .doc . … and use it with Haiku ?