The l4d_zelda.zip file you have requested: Maps Levels Missions / Coop Maps / Zelda Labyrinth - 4.73mb 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:
Obtain gold keys and complete puzzles / objectives to unlock doors that allow you to progress further into the dungeons of doom. Includes moving traps, and even a boss battle against a giant animated robot dragon that fires lasers, moves and even ram The Legend of Zelda: A reproduction of a map of a labyrinth!