I press Func/Set and scroll down to "motion lua" and can't do anything with it. When I press shutter release the camera fires and then shows at the bottom of the screen " started /finished"
After scrolling down to the script of your choice,
select the file with FUNC/SET (this acts as your "Enter" key); to start the script you've selected this way, press the shutter button...
You'll see the script title on the LCD screen...