Guides to Objective maps?

[Freax]

Im kind of new to the game, so im wondering if there are any guides that show you what to do in maps like Subway etc. I havent seen any on the forum yet, and it gets confusing when 6 survivors on the map have no clue what to do.

[samhain]

Guide for subway
http://youtube.com/watch?v=vLAm14qlqqw
i really dont plan on making any more zpo guides. but as of now that is the only objective map