Thanks for the input fullmetal5550,
I was expecting that was so but was not sure if it will change the .exe file if I select to install it since I would like access to the weapons and goodies from the expansion pack. IF they can be spawned in singleplayer that is..
If not and if it will change the .exe where the trainer might not work then I won't install the expansion.. It's that simple since I don't play multiplayer games.. Much...