I've been modding Left 4 Dead 2, and Team Fortress 2 ever since Netham's tool was released, however Left 4 Dead 1, I still can't get to work. I have wasted countless disk's, and even more hours attempting to get Left 4 Dead 1 ISO Mods working, however they still don't. Maybe I have a corrupted ISO or something, but it seems that it is not done the same way as Left 4 Dead 2, or Team Fortress 2. If anyone could provide me with a way to mod Left 4 Dead 1, I would be very thankful.