hey, this is a very irrelevant comment since it's not DA related.
I saw a post you made on a L4D2 custom campaign and you explained a problem you had that when you subscribed to it your game crashed.
The only reason I was inclined to leave you a comment is because I have had the same issues with a ton of workshop mods and figured out as to why this happens.
Apparently steam workshop has a big issue where it fails to properly download subscribed items to your PC, thus making L4D2 crash when it tries to sync with them. And no matter if you unsubscribe and subscribe again, Steam will tell you that the files were downloaded correctly even though its BS and your game will still crash.
I been trying to find a solution so that Steam can properly download the mods I want but sadly havent found one.
I did find a side solution to it, and that's to go to l4dmaps.com and manually search and download your files (then put them in the folder program files/steam/steamapps/common/left 4 dead 2/left4dead2/addons.
Sorry for the kind of random (but hopefully helpful) wall comment, but I wished someone had explained to me last week that this was the problem so I felt inclined to help.
Have a good day and game on!