For Mac users: When you create a program entry for Safari, for example, you would think the path to the Application is probably: /Applications/Safari.app
and logically so, because when you browse the directory you aren't allowed to go into the Application's hidden contents. However, this is not the correct path. Right-click on an Application and do "Show Package Contents". The correct path to the Safari application is actually:
/Applications/Safari.app/Contents/MacOS/Safari
Not very intuitive, I realize, for you Mac users out there. Maybe in a future version there will be an easier way to access these hidden Application contents.