Ugh... sorry for the triple post. But I went back and was clicking around the registration dialog (wondering why sometimes the button said "Register" and sometimes "Update") and this time the serial worked. There is 0 chance that I was mistyping it earlier, but at least it works now! I'm sure you'll get other repro cases ;-) ~SDC~
Oops, forgot to add... To forestall the obvious question, I was entering the serial for GalCiv, _not_ for drengin.net. ~SDC~
Frogboy said "You can buy the game at EB or wherever, then just come here, download SDCentral, put in the serial # from the back of your CD case, and download it." I bought the game retail, installed, then installed SDC. I pulled up the register dialog and my serial had already been entered, which was fine. However, SDC complains that it's an invalid serial number. The dialog mentions copy/pasting from the purchase email, so I figured that registration was only necessary for internet
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