Trying to load the Cursed Apple in sandbox mode causes massive visual glitches in the rest of the game (Reproducible)

[Vesk]

I tried to load the Cursed Apple in sandbox mode using `map street_test`. I think it loaded, but when it did I only got a black screen. I could move around but all I saw was pitch black (besides the HUD). I then disconnected and tried to open the Hero Sandbox, but the textures of everything were really messed up.
Perhaps these were some kind of normal maps, or something like that. It was fixed by restarting the game, but I was able to reproduce it exactly by repeating the steps above.