The death_rails_131209_3682.zip file you have requested: Maps Levels Missions / Coop Maps / Left 4 Dead Co-op Map Death Rails - 1.44mb is not available. Perhaps try browsing all files for the game Left 4 Dead and upload any files you want to share or are missing. This is the only information we could locate:
Type in map "The Cabin to start the campaign. the second map start a new round because it dont load right the first time. You start in a cabin and you have to get out of the city by taking the last working subway train out of the zombie infested city.