1. What do you think CDFinder could gain from being ported to Cocoa? 2. No, CDFinder will not support the .sitx format. It already does support the native .zip format that Apple is using in the Mac OS, and as the .sitx is far from being widely used lately, the effort is not worth it. Also, the .sitx format is heavily encoded, non-standard, not-documented, and therefore more than hard to decode. Stick with .zip! It is built-in, and it's free. And PC users can read it, too.