Ok, Thanks! Well, I guess the solution you are referring to will do well when it will become available.
I guess the campaign manager copies the skin that you choose to the proper location before starting CFS3, so that there is no way to set it in the mission file, but you could still copy/paste manually the skin of your choice before starting your MP session. Could anybody that knows about the process of skin selection during campaign mode briefly enlight me about that? Thanks :)