You have accidentally enabled 'Full Screen At Startup' in the 'Output' menu. This happens when your computer is not connected to an external display device (projector or monitor).
To disable 'Full Screen At Startup':
- Launch Modul8.
- Press the key combination 'Command (Apple)' + 'T' to exit full screen.
- From the menu select 'Output > Full Screen At Startup' so that it is unchecked.
Next time you launch Modul8 you will be presented with the expected Modul8 interface.