Ok it works.. thanks again.
Of course I had to turn on the relay power, which is normally wrapped in the Multilapse scripts..
and it gave me an image named
IMG_1374.jpg, instead of a neatly formatted and time stamped multilapse version like this
mycamera-2018-08-14-19.04.39.jpgand there's no retrying the camera if the power fails first time, or error messaging, or temperature readings, or logging.. all the things I love about Multilapse.
So, thanks to you I feel I understand more about what's going on so I will see if I can apply what I've learned to adapting Multilapse 'properly'
I think if I modify the 'shooting loop' to include the camera init funtion (which includes switching to rec mode) and then a switch to play mode at the end, it just might work..