It's worth pointing out that although the Myst 3 patch will let you run the game under OS X, it introduces a bug - you can't play with two monitors. When I played it, occasionally when I went to click on an item in the game the Finder would pop to the foreground, as if the cursor had wandered out of the game window.
I had an email conversation with tech support, and was eventually told they just don't support two monitors. Really annoying.