the gskeydisc proof-of-concept requires the sending of spoofed packets so it's all useless if you are not an advanced user who knows very well the devices that connect you to internet and how to configure them, the bypassing of the restriction on windows and moreover the testing of the successful sending of a spoofed packet.
I repeat, if you don't know what are the spoofed packets you can do nothing.
if you have that requirement then the usage of the tool is trivial:
gskeydisc <server> <port> <pid> <cd-key_or_MD5_hash> <client_IP>
where:
<server> is the game server where you are connected
<port> is the port of the server
<pid> the pid of the game, watch
http://aluigi.org/papers/gspids.txt (2264 in your case)
<cd-key_or_MD5_hash> the cdkey or its md5 hash used by you and your friends
<client_IP> your public internet IP address (like
http://www.whatismyip.com)
example:
gskeydisc 1.2.3.4 5447 2264 XXXX-XXXX-XXXX-XXXX 123.123.123.123
gskeydisc must be used by any player that uses the shared cdkey (or at least the first one if you are in two) just after having joined the server so that the cdkey gets freed immediately.
note that the players with the same cdkey can't play on the SAME server because it's a server-side limitation.
full details and example (section 3 and later 4):
http://aluigi.org/adv/gskeydisc-adv.txt