played the first one... was really shit.
this is what you're talking about right:
http://blendogames.com/older.htm (at the bottom)
there is a train sequence but it's little more than running across the top of 6 cars while monsters spawn behind you.
i was thinking more where you're fighting through the cars themselves with different types too (cargo ones, passenger ones, fancy passenger ones, etc...) where monsters can break in through windows or in the case of cargo containers, open those side doors or something.