Ammo Pack Entity Crash

I'm afraid I've hit another wall in mapping. When trying to place any ammo pack entity, Hammer simply crashes. I found forums talking about a similar bug back in 2012, saying the solution is to refresh SDK content. I did that, but it didn't work (I'm guessing it's because certain files were moved around during the Steam Pipe update a while back). I'm afraid I've run out of ideas on how to fix it.

It worked like a charm. Thank you so much!