Although TimeShift's multiplayer mode works well over OpenSpy, unlike the Steam and retail versions, users with the GOG version appear to all be using the same CD key, preventing them from joining games where another GOG user is present.

OpenSpy does not do any key verification, however the game checks cd keys directly with other users, thus we can work around this issue if the cd key can be changed to something random. The Steam and retail versions store the cd key in a registry entry, however no one I know with the GOG version has been able to find it, as it uses different locations for the game. Anyone here able to help?

Solved. The game seems to be reading the key from the same registry location as the Steam and retail versions even though the installer isn't creating it.

creating the key at
`[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\sierra entertainment\timeshift\1.00.000]`

then a string value for the cd key
`cdkey=XXXX-XXXX-XXXX-XXXX-XXXX`
where the X's consist of random letters & numbers allow GOG users to play online over OpenSpy with no issues.