呢個MAP 係由Matthew Lourdelet 造的自制地圖
與L4D OR L4D2 的劇情無關
參考 http://www.l4d.com/blog/post.php?id=5019
引用"Matthew Lourdelet (2 Evil Eyes) has been working on a new community campaign – Cold Stream"
"For this DLC we start with wanting to experiment by releasing a map pack that wasn’t about story"
唔洗估啦 , 官方講左會出返舊MAP
Dead Air
Death Toll
Blood Harvest
Crash Course http://www.l4d.com/blog/post.php?id=5054
"With the announcement of Cold Stream we also mentioned that we will be porting over additional Left 4 Dead 1 maps"