Sound Studio was rejected again because of a permissions error with the files in the app bundle. The reviewer got a “unsigned app” error when trying to launch the app, and I verified that the problem only happens if you open the Installer package and install it on another computer. The source of the problem was that many resource files in my project had their permissions set to be readable only by the user, and not by the group or others. (You can use “ls -l” to see the permissions, which should be rw-r—r—.) To fix it, I ran this command in the Terminal on all the files in the project:

sudo chmod -R =rw,+X *

So this is another thing to check before you submit to the Mac App Store.