There is an unhealthy amount of invisible walls here.
Also, this map is VERY confusing, I would add more fencing and direction signs so it isn't so open. Also, please differentiate wooden platforms which you can and can't stand on, I was pogoing on places where I was able to stand. Oh, and Source doesn't like upside-down water...
Missing texture:
https://imgur.com/a/pMksfYou can stand inside this pillar:
https://imgur.com/a/BipdR