As the README already states:
Numpad 3: No Reload - toggle on in the game and most weapons will not use ammo.
So are you saying the new trainer option of No Reload doesn't work on Semi-auto weapons in Campaign but works fine in DLC. And the old trainer did the exact opposite? That is really weird I must say. It must be something with the code in the game. I am sure @Caliber will fine some way to fix it if it can be fix. But if it can't be fix, I think that will be OK as well. @eta3minutes, the No Reload option do work on other weapons in Campaign mode other than the ones you mentioned right?