adding multiple pieces of skins to one model????

[alreadyused]

Currently i have created a simple model and made a few skins one for each part of my model. However when i go to mdl notepad and enter in the textures only one skin is applied to the whole model instead of what i wanted, which is three different skins. I use gmax to model. Can anyone tell me how to edit in mdl so that the model uses all three skins?? Or am i doing something wrong prior to editing in mdl notepad? :? any help would be appreciated.
thanks, alreadyused