Garrysmod Crashes while Loading Custom CSS Maps

Okay, so yesterday I downloaded 2 css maps from and put them into my Gmod maps folder. I have CSS installed and I can play all of the regular CSS maps in Gmod with no problem, but when I try to load up the custom maps it crashes to desktop during the loading screen and gives me the “HL2.exe has stopped working” error. I tried deleting everything in my garrysmod folder except for the maps and addons folders and then loading up Gmod and loading up the maps but that didn’t work and then I tried with a fresh garrysmod folder and still nothing. What can I do?

Do the maps work in CS:S?

Maybe he pirated the game. I don’t know…

I did not pirate either game. And yes, they do work on CSS.