About a year ago I bought
Rome Total War: 2 Emperor Edition for my Mac through the App Store. I bought the DLC
Greek States through Steam. I have an activation key for the DLC but when I enter it on Steam, it says that I need to activate the base game first, but I can't get an activation code for the base game because App Store doesn't give you a code.
Is there a way for me to activate the DLC on App Store or the base game on Steam?