Hey! I'm not the dev on the project but I ran into this issue on my own game. The solution should be to change your Mac OS security settings to allow all applications. Unfortunately Apple has hidden this option away pretty heavily so you'll have to go through some steps to enable it: http://osxdaily.com/2016/09/27/allow-apps-from-anywhere-macos-gatekeeper/
That *should* fix it ;)