It will work CS, but will have no effect on other players, since the server does not have it. Be aware that changing graphics COULD get you kicked by PB. (I dont know what PB actually checks)
Actually using the BF mod tools you can pretty much build yourself an entire mod using nothing but those and Gmax, maybe battlecraft for maps and stuff, still can't find a way to import into milkshape though, which I prefer for modelling.