To use cheats you first have to edit config.cfg You can find it at this location: "*:\My Documents\18 WoS Pedal to the Metal". First make a back up of the config.cfg file. Use notepad to open the file and change it. Change this in the file:

uset g_console "1"
uset g_developer "1"

When you changed it you save the config.cfg file. Start a new game and press ~ a window appears on your screen type one of the codes underneath this message and then press "enter". You can close the window by pressing ~ again. Enjoy your cheats!