Trying to fix another few errors

Moved a rebel spawn that was getting stuck in some crates that wasn't supposed to be there.

Replaced some missing models that didn't get rendered with built-in models to give the map a fuller look.

Finally got around to patching up some small mis-textured areas on the map. I also made the pit at the east-most part of the map possible to get out of by ramping a small part of it.