I had the same problem as his. I then tried out the command you suggested and now it's working as normal ever since. Thanks.

Hi, I'm the guy who was having this problem that SNEK is talking about. Only the gamemode you created makes my game crash when I select the MP5, even with all of my addons disabled. But I was able to see it, hear and see my friends using it in action. So I'll try hl1_cl_fixchrome 0 and see if that fixes it.

The command works!

Is Half-Life Source mounted or are you using content addon?

We’re using the content mods to get the game mode working. We do not own HL: source so that’s why

Fixed. You can set hl1_cl_fixchrome back to 1

Thanks dude!