Disable compass in Zen subtheme
So Zen uses zen grids for its grid (in some cases) and that has a requirement for compass/css2/images. if you aren't using zen grids, you can disable that dependency.

Another option could be that you can try to delete/rename the config.rb file entirely, as CodeKit may see that and automatically assume you want to use compass to compile your Sass.

A third possibility could be that in the bottom of _init.scss (STARTERKIT/sass/) it pulls in zen, along with alot of other compass extensions. try disabling zen along with the others you already disabled.