http://bugs.winehq.org/show_bug.cgi?id=12536
--- Comment #10 from Martin Wolf natoforce@gmx.net 2008-04-19 22:03:02 --- it seems that the installer of the main game (dawn of war) is different (older?) to the addons.
I was able to install DoW-Dark Crusade and DoW-Soulstorm flawlessly. (asked for CD Key and started fine)
According to APPDB im not the only one who has this problem with the old DoW since it seems to be a common practice to extract the Registry Keys from a windows installation and importing it into wine registry.
maybe you should take a further look into this.