Additional fixes and patches

Thanks to some steamed help from Tenzinite and tgn8r, we found some more bugs that are now fixed:

- The F5 key (for if you get stuck or fall off the map) now works again.
- Fixed a bug that would mess up the locker in the Workshop.
- Fixed a bug that would mess up the Kryptex in the office.
- Fixed shader that would generate black squares where things should be hidden.

Still working on whatever causes the black nothing bug, it has been haunting the game for a while now, and can't seem to get rid of it...