I figured it out. Apparently the skybox was all screwed up so I just copied the skybox from a new map and pasted it into the current one. It works now, thanks though!

When I build my mod and run it after building it, I come am spawned into the game and all the walls around me are invisible, and my knife does no damage; also take no damage when hit by zombies. However, the pistol does kill them. I've posted an image below showing the issue, please respond with an answer if you have any ideas to why this could happen.
Thanks!
https://giphy.com/gifs/jkYpTMF13O1w5y0znO/html5

I tried rising them up 1 square with 8 grid, and kept them not out of 128, and that still didn't work, I have the volume, the barriers, the keys of the zombies and volume all correct.. Not sure why it won't work, but if there's another thing to try, I'd do anything to try it

---

Double Post Merge: October 28, 2017, 04:43:20 pm

---

I tried all of those, and nothing worked...

EDIT: I got the volume fixed, now I just need some help on the pathnodes... I have then around my map, and leading the zombie to the barrier, but when I compile the map, they don't move as they would if it were to work...

Please help??   

I am adding the zombies and volume into my map, i then put in the keys and values, then i save it and compile it, then it does nothing and I try to open my map in radiant and it doesnt open. It says "worldspawn does not exist" or something. Help? This has happened to me 3 times and i've had to restart 3 times and its really getting annoying.