Hello Frank Sinatra!
Nice to see you here.

It's always a huge challenge to play against you (and a pleasure to play
with you

).
Anyway, I think your problem isn't really that big. I remember when I needed the game on my notebook, I didn't install anything at all. I just copied the whole UT2004 folder (with all contents) from my PC to my notebook. Then I ran the UT2004.exe file in the System subfolder and voilá, it worked. Most of the registry settings are being restored when they're missing and the key you entered when installing the game on your other PC should be located in a file somewhere in your game dir. However, you won't be able to uninstall the game from the Control Panel, of course, but instead, you'd just have to delete the UT2004 folder with all it's contents and remove the registry settings.
Well, I did all this a few years ago, so maybe I'm mixing it up with "Unreal Tournament", which I also played at this time. It works 100% for UT, but I think I also made it for UT2004, just because I was too lazy to install the game (and all patches, maps, mutators, etc.) from scratch. Anyway, it's worth giving it a try (can't harm anything). But still, I would uninstall the UT2004 demo before doing it...
Concerning Game-Spy: Ghost, how can you be that naive? What, do you think, is the reason they're offering this service at all? How can they finance all this? I
guess (that means I don't really know it) they're collecting all kinds of information about you and your habits of computer usage, probably cross-connect them with other information and sell them to some advertising company (or worse)... That's something I
really don't like about UT3 at all.
Coco.