Those screenshots doesn't look anything like the map I downloaded, haha. I think you got your maps mixed up.
Anyway, first off, don't use capitals in the file name - Linux servers don't like that.
I would also add some basic lighting using a light_environment entity because all your surfaces use the same texture and it's very hard to tell what's where. On that note, please use more than one texture so not everything looks the same.
Third, I can tell it's leaking very badly....make sure you're sealing your entire map in world or skybox brushes so nothing can see or touch "the void". This can be prevented by getting rid of all the tiny gaps in your brushes and keeping your vertices aligned and on the grid.
It's also huge and open. That's bad news for optimization and too much fun for snipers.