An idea I came up with after watching a show. Thought it would be possible to create with Unreal Editor, so here it is. I put it all down on a scheme map image with notes all over the place. The image is rather large, but that couldn't be helped.

A few things that I should point out, first is that that elevator icon on cart 8 shouldn't be there.

Weapon Stations are marked by the thin x's. Elevators by the up and down arrow within the circle (arrow shows the direction the elevators operate). I haven't marked in ammo, health or super pick ups as they'll depend on the carts design.

The vtol only advances to drop walls when they've dropped from destroying the clamps holding them, marked by the black ?, not when brake overrides have been destroyed.

If you destroy the control panel and hit the secondary emergency brakes without destroying all the overrides, the train wont stop until all the overrides have been destroyed.

The train will bend as it goes around a curved section of the track (naturally). This will sometimes make cart 2 unable to see the rear cart, thus protecting the vtol momentarily.

Finally, there is a ramp to get onto the roof of cart 2, so defenders can take cover there.