That just crashes the game

My question is why doesn't it work when i change the parameters and colors of the fog in the existing fog script or the map properties editor?

Example in the display00.wdl the code looks like this

// section: Fog Settings

// entry: Fog color Index
// help: Select the fog color from the Map Prop panel in WED.
// cntl: spin 0 5 1
// id: 52
fog_color = 0;

// entry: Fog Start
// help: Percent of clip_range until fog start
// help: There won't be any fog closer than fog_start
// id: 50
camera.fog_start = 75;
camera.fog_start /= 100;
if(camera.fog_start < 0) { camera.fog_start = 0; }


// entry: Fog End
// help: Percent of clip_range until fog end
// help: The world will be all foggy beyond fog_end
// id: 51
camera.fog_end = 90;
camera.fog_end /= 100;
if(camera.fog_end < 0) { camera.fog_end = 0; }

camera.fog_start = camera.fog_start * camera.clip_far; // fog at 80% of clip_range
camera.fog_end = camera.fog_end * camera.clip_far; // fog till 90% of clip_range
}

I change the fog color to 1 and I assume that relates to the 1 slot in the map properties fog color editor

I changed the start and end ranges countless of times in countless of combonations and nothing has any effect whatsoever.

What am I missing?