"When you play your first match or PUG in a CyberGamer server, your STEAM ID/GUID will automatically be collected and synced with your CyberGamer Account on the website. The following games are supported: Call of Duty 2, Call of duty 4, Call of Duty 5, Counter-Strike Source, Team Fortress 2, Soldier of Fortune 2 and Left 4 Dead (1&2).
If you really need to have your GUID/STEAM ID changed, open a support ticket and an admin can change it for you. We prefer this does not happen often as there is no way to verify that the GUID/STEAM ID you are providing is actually yours, whilst the automatic syncing cannot be faked."
Posted on Thursday, 20th May 2010