Changing the textures under the surface tab can be done. Just not to the degree I think you are lookng for in Studio. but if you are tryung to change say the tomy as to the hip nope  not in Studio you would need somthing like photoshop and recreate the textures you would like  save them then inport the new textures under the surface tab what you seem to be looking to do is far beyound my talent. I would love to be able to use any 3d Program but I am a click and go artest.