So after buying the Whole can o worms as well as 3D during the Interplay summer sale I've finally gotten around to playing 3D for the first time

Now, my question is: How exactly do I enter cheats in this game?

http://uk.gamespot.com/pc/action/earthwormjim3d/cheats.html

The codes that are posted here and supposedly for the PC version, I try to enter the cheats - nothing happens

I disable all of the keys to make sure they dont do anything in the game and enter the cheats - nothing happens

Am I supposed to enter them under specific circumstances? or in some sort of special way?

Any help would be greatly appreciated

Thanks!