Ok, I uploaded a new version of the installer. Run the uninstaller, install the new version. Uninstall it again.
Then reinstall it. The first thing you should see after you run it the first time is a dialog box asking you to select your Galciv 2 directory. Once you have selected this, everything should hopefully run fine. If not, there will now be an error.txt file in the install directory, which should hopefully shed some light on where the problem is.
Once again, here is the link: Link
Thanks for your patience everyone. Sorry that I didn't have it working from the start. With any luck, it should be up and running quickly.
PS for CHAORAIN:
No, this is completely unofficial. I'm not affiliated with Stardock in any way.