Simple. Just have the IP address (or subnesk mask, or gateway) you wanna convert.
Let's say it's 192.168.0.2
Write it in hex : C0.A8.00.02
Then remove the dots, and write it backward :
ip: 192.168.0.2 = 0200A8C0
Oh, and don't set the Xbox Ip address as the Gateway. The Gateway should be the PC's (or the Router's) IP address...
I have one small Q : How does one debug a retail game? I remember seing people debugging DOAX some month ago (when the "nude hack" was created), but I couldn't understand how they did it...