1) The first error you can just remove the second attacher joint in the xml.
2) The lights can be fixed but then I lose the dashboard lightup inside the cab. Something changed from 15 to 17 and so I just left it as is. Shouldn't hurt anything its just a warning about the change to the method getLightColor
3) FillPlaneGeometry shape error requires a rename of the fill volume shape in the model itself. Requires to be rebuilt in blender so a lot more effort to elliminate but should work just find as is. Just complaining about the old naming.

Yes, you can skin this mod for the Masey Ferguson or Gleaner versions. I was specifically interested in the Challenger version since it uses a Caterpillar engine. Should be able to just pull the textures out of the old fs15 and reskin. The area you will have trouble is the header but you could just strip decals off and replace color to match masey or gleaner.