You can get the data cheaply from GOG also, if you have a little extra money to spend DXX-Rebirth can work with either the PC or Mac data, regardless of the operating system you're on at the moment. Your options there basically boil down to using an PowerPC emulator to run an older version of Mac OS to install it, or find a PC CD-ROM instead. The included docs nicely explain where everything goes, but it also describes difficulty getting the data. Unpack the DMG which should install the program for you. Someone in the Descent forum typed out this: These two games were tested using the software 'PlayonMac' I'm still pretty new with the iMac stuff. I think it had something to do with the graphic card, intel or something. But the original (iMac edition) doesn't work. The Descent 3 game appears to work, a game dated back in 1999. I am hoping to get the classic Descent games to run on the iMac.