Alright, I went threw it on a server I created, here's what I think:
Great map overall!
There are some places where you are totally safe from trains (while holding the intel):
-The ledge above where the trains leave the play area.
-The ammo pickups on the raised platform.
Some glitchy things:
-The drop to leave spawn from the 3rd story is a bit tight. Mr. heavy might not be able to get
through.

-The supply box placement as you round the corner in spawn is a bit interesting. I bumped
into it once, and it didn't give me ammo as I rounded the corner a couple times.
-Sticky bombs stick to the invisible wall where the trains leave the play area.
Also, if you follow one of the raised platforms on either side, there's a drop at the end, and you are able to get in behind the trains. You won't last long, but I'm not sure if it's supposed to be a glitch or not.

But for the most part, a great map! It looks like it's gonna be a lot of fun to play with people.
Ps. What's with the random Gman just outside the map? I suppose it's his train station.

I got hit out there by a train a couple times and I was like 'wtf?' lol.