Can't Use Left 4 Dead 2 Maps

Everytime I try to create a Gmod game with a Left 4 Dead 2 Map, It just closes and NOTHING HAPPENS. Does it happen to anyone, or is there a way to fix it?

Left 4 Dead maps are not useable in gmod because the games use a different base. If you want to get maps for Left 4 dead, then just search them on gmod.org on the internet.