If any Mac users are having trouble opening the application, it looks like something wasn't handled correctly during the build. You need to open Terminal, cd into the folder that contains SU, and paste this code
chmod a+x SomeApp.app/Contents/MacOS/*
replacing SomeApp with the name of the SU application.
Then it'll open just fine.
chmod a+x SomeApp.app/Contents/MacOS/*
replacing SomeApp with the name of the SU application.
Then it'll open just fine.