Playing Gabriel Knight: Sins of the Father in OS X - Short Version

Here are the steps I took to play Gabriel Knight: Sins of the Father on my Mac. This tutorial is specifically for running the version of the game from GoodOldGames.com, NOT for the original CD or for other versions obtained via the net.

Step 1: Get the game
Purchase and download Gabriel Knight from GOG.com. Install the game onto a PC. As far as I know, this can't be done using a Mac without emulating Windows on the Mac. Find the directory called "Gabriel Knight" containing all of the game files and transfer them to your Mac, probably via a portable hard drive. Make a new directory in your "/home" (or "/username") folder and name it something like "dosgames". Save the "Gabriel Knight" folder to "/home/dosgames".

Step 2: Get DOSBox
Download DOSBox for OSX to your Mac and save the application in your Applications folder.

Step #3: Configure hardware settings
Open DOSBox and enter the following commands one at a time:

mount c ~/dosgames
c:
cd gabrie~1
install

This will bring you to Gabriel Knight's hardware configuration screen. The best options for me were "VGA or IBM PS2 - 256 Colors" for graphics, "Sound Blaster Pro" for Music, and "ThunderBoard" for audio, but different options may work better for you. Just make sure to select options that have check marks next to them.

Step 4: Optimize DOSBox for the game
Open "/home/Library/Preferences/DOSBox 0.74 Preferences" with TextEdit. At the very end of the document, beneath where it says "# You can put your MOUNT lines here." write:

mount c ~/dosgames
imgmount d ~/dosgames/gabriel_knight/GK1.gog -t iso
c:
cd gabrie~1
sierra

Save the document and exit. Now when you open DOSBox, it will automatically start Gabriel Knight. If you don't want it to start automatically, delete "sierra" from the "DOSBox 0.74 Preferences" document.

This is what worked for me; hopefully it's of help to you!