As far as we know, Jehezekel is correct that the save game files from the add-ons (most of them anyways) need to be uncompressed in Mac OS X. I suppose the reason for this is that .sitx is too new a format for OS 9. We've had this problem in the past with a board member who used OS 9 on his computer to play Cythera.
What operating system are you using? Make sure that you have the most recent version of Stuffit Expander. If you are using Mac OS 8 or 9, try downloading
this version. If you are running Mac OS X, you can select the different Mac OS X versions from
this page (click on the version number next to the Information Related to Version box).
I'm not sure if that will help you, but you could also try unstuffing the file on Mac OS X and transferring it to your other computer.
If none of those things work for you, let us know.
I hope TwoJacks comes by later, because he was the one who had this problem, and I can't remember if we solved it or not. I think that we can send the uncompressed files via email, though.
This post has been edited by The Wizard: 04 June 2009 - 01:04 PM