On my Mavericks machine it says the app can't be opened because it's damaged. Any ideas?
Sorry for the inconvenience. It is the combined effect of a signed App with modified Info.plist, when it is also quarantined. One way to fix this, is running xattr -c on the Utility or on the .zip file to remove the "com.apple.quarantine" attribute.
Note however, that this is roughly equivalent to allowing an unsigned application to run. Similar caution should be applied.