Thought I would share this for any Mac users that stop by. This is how to do a full install on Mac OS X running classic mode. Someone posted way back about the medium and full installs mysteriously disappearing after installation.

First, trim your extensions using extension manager. Keep only the quicktime and open transport extensions. Disable everything else, including all control panels. Its best to make a new extension set, called "Starship Titanic".

Launch the installer, select FULL install. Make sure both checkboxes are checked. Select your game destination folder and then start the install. You will be prompted for disk 2, and then disk 3. Then you will be asked to insert disk 1 again, but DON'T! Instead, use the finder to navigate to your install directory and DUPLICATE it. Once the copy is complete (you should have a "Starship Titanic" directory and a "Starship Titanic (copy)" directory), insert disc 1. The installer will continue and then delete the original "Starship Titanic" directory.

Then launch the installer again, select the SMALL install, check both checkboxes, and select a destination folder. The small install will create the necessary preference file. Finish the game installation and then quit the Quicktime installer without installing it.

Then, using the finder, navigate to the small install folder and delete it. Now rename your full install directory to "Starship Titanic".

That's it, your done! You can remove the disc, put them away, and play the game!

Thanks you. This sounds complicated but do-able. (I'm not on Mac, so: no clue... )
This will be probbably helpful for any Mac user who comes along this forum.

greetz Capt. ed