Well, I have been advised to review in-game experience only. I would have done that but after the Installation procedure no game appears in the application directory of my Mac. Even worse: there is no way to see to which directory all the files have gone which have been copied to my HD. I have already searched the STANDARD (!!!) locations for such packages without success. Instead of playing Alpha Centauri I will now spend some time to remove this fine piece of software from my computer. All in all I advise the developers of the Mac distribution to quit their jobs and instead apply for one in the wood processing industry. In the case I missed something and this is actually an extension pack only it would have been good to state that in the description. Something like "Note: You need XYZ to play the game." would have done the trick. Might be a excellent game but I will never find out....