Hi Carbon_Shriek, please try doing a system reboot and also check very carefully that you are actually launching version 3.1 and not the original version 3.0 .

What happens if you launch it directly from your downloads folder?

What you are describing is exactly what happens when running version 3.0 on El Capitan but I have not had any prior reports of it happening with the updated version 3.1 .

- Michael