Leave the MAP screen and come back and you will see it has increased. Numpad 5: Add Level - press TAB to enter the MAP screen and note the current value. Numpad 4: Add XP - press TAB to enter the MAP screen and note the current value.
Numpad 3: No Reload - toggle on and many weapons that would otherwise need reload will not need reload. Numpad 2: Unlimited Ammo - toggle on and many weapons when you fire them will have unlimited ammo. This will not save you from scripted deaths or deaths where you miss acrobatic maneuvers required by the game. Numpad 1: Unlimited Health - toggle on and most things cannot damage you. Launch the trainer first, then launch the Game and then Press F1 at the Main Menu.