Gotta admire you for using this kind of style! Quite interesting in the themeing I imagine you're going for, especially in comparison to other maps I've seen. That being said, a lot of the area past first point up to near last feels quite... cramped and claustrophobic. I have yet to playtest this on a server full of people, but I can only imagine how some of those tight corridors will play. Can't imagine some parts of the map will be very fun to fight people on.
Also, the walk from Red's spawn to the first point is quite a ways, I feel. Especially considering that you could get lost if you're not following just the tracks. Perhaps a more forward spawn would help with this? Though, that is entirely up to you. I just feel like holding the first point will be quite difficult without an Engineer being progressive about keeping up a helpful teleporter. That being said, feel free to take my opinions would a grain of salt! You're doing good so far.
