If you select the Visualize button on any of your Button's Button component, you should see the following navigation path (I have disabled the background image to make it a bit easier to view):
This navigation setup allows significantly more navigation range that the setup I described at the beginning of this example. This is because each button has its navigation set to Automatic by default, and Automatic allows multidirectional navigation. Let's make our navigation a bit more linear and make our Play Button the First Selected Button in our Event System.
To set up the navigation described ...
