Hello,
There is an app name "Start10tweak.exe" that is inside your installed Start11 directory (usually "C:\Program Files (x86)\Stardock\Start11"). If you click "Unload Start10 now" button. That should unload Start11. You should be able to reload Start11 by running Start11.exe again and restart Explorer.exe.

Thanks
Basj,
Stardock Community Assistant.