This is for those of you wanting to play lan without having to worry about the CD Key check. First, open of the GSRouters.dat file in the /system directory with notepad. You'll see this:
[Servers]
RouterIP0=gsrouter-mtl1.ubisoft.com
RouterPort0=40000
RouterLauncherPort0=40005
RouterIP1=gsrouter-mtl2.ubisoft.com
RouterPort1=40000
RouterLauncherPort1=40005
CDKeyServerIP0=gscdkey-mtl1.ubisoft.com
CDKeyServerPort0=44000
Simply change everything to whatever you want. I just used localhost and some wacky port number like 98372 for each one. Simply save it and be sure to change the file's attributes to Read Only. I'm able to play lan without having to unplug my cable modem just fine. No CD Key required, just click the green check box and it will time out after a few moments and let you continue. [Nforce]