This .cfg file will reset the fog level every time the player moves forward - effectively preventing people from increasing fog level ingame.

This file has limitations though - since .cfg files are NOT sent when playing on line, it is completely innefective for ingame distrobution of maps (but so is your carefully set fog, so it doesn't really matter). Also, the user could just delete the code, and this code will NOT work if the user has a custom key binding for forward movement (unlikely).