This was explained to me by a cracking guy (you know who you are 🙂) I havent personally tested but these were the details. For linking get a cheap router Dlink or similar, routers have a settings option, normally accessed from the web browser and typing in the DHCP address (normally its 192.168.0.1 or similar), once inside the configuration you need to setup the LAN address range correctly, the DHCP router IP should be 192.168.138.254 and the IPs the router can assign should be 192.168.138.11 to 192.168.138.20 (aka the cabinet range), so for example once set the first allocated IP to a PC should be 192.168.138.11 and the next .12 and so on. You also in test mode, need to keep them on the same group, but one needs to be Red, the other needs to be Blue - once that is done you can play in link mode.