From: London England
Regrettably, the game, at least the ones downloadable from GamersGate, seems to be broken. I have tried installing it on three different computers. One running Windows 7 32 bit, one running Windows 7 64 bit and one running Windows 8.1 64 bit.
All report the same "problem with serial number" message and refuse to load.
I don't feel I can complain too much about a free download, but perhaps you should consider withdrawing it from GamersGate.
However, if the version from Matrix Games also fails to load, I would be properly annoyed. I don't feel like paying money to run the experiment.
It's even money, that the light at the end of the tunnel is an oncoming express