I have seen ski tracks along the stony brook route several times over the years all the way from the junction of the AT. I expect that most folks go straight at the crossing and follow the old route out to the development, although with the exception of the river crossing to the new route, the new route is pretty flat. I would be less certain about the stretch on the AT up from the Stony Brook Junction to the height of land. There are several spots where a wrong decision could make for a very bad day due to adjacent cliffs. I realize that there are folks who can routinely ski incredible stuff so I am not saying it hasn't been done but would probably be in the realm if you have to ask you are you are probably in over your head.
If you haven't done CM trail from Gorham in the winter be prepared for a long slog, its on several folks lists as one not to be repeated due to the numerous Puds.