Go to Stardock Central, look under Tools/Register Products. Then under Products select GalCiv 2 and check the serial number there. Even if you enter the correct serial number in the game launcher, it doesn't matter, the game will pull the serial number from here in Stardock Central. My SDC had a totally different and strange serial number here. Update the serial number here in Stardock Central, then update it in the launcher. Then play a one turn Metaverse game, retire, and see if you can then upload it to the Metaverse. That is how I got it working and tested it to make sure.
Hope this helps.