There are many maps l4d 1 & 2 have already been ported, but since the famous update that to put an end to the use of gm_mount, these maps dont work no longer. Try to run one, nothing happens.
Tips: Basically just rename them! (the bsp file) Consider the map hospital here --> http://www.garrysmod.org/downloads/?a=view&id=76022
Her name is “l4d_hospital_interior”, rename her to the “hospital_interior_gmod” and you will see that it will launch when you click on it wink
And here’s the proof:
This model was released well after the famous update.
I discovered it because I renamed some of the maps that I had ported myself. I had added “l4d_” at the front to put order in my icons. And suddenly she’s no longer starts.
p.s. Unfortunately you gonna have some display bugs because those maps has not been reworked and there are some incompatible textures. But well…