Hi Wapping. I didn't have notifications on.
I appreciate everyone's input since last April.
I never found a way of using W3W in software. W3W needs an API to get the GPS co-ordinates and costs money.
However, the request is now a moot point because TrailVidz has put GPS con-ordinates in every map pin.
So, the GPS data can be put in a list, changed to KML, edited in GoogleEarth and then saved as GPX file.
It's straight forward when you have done it a few times and it means you don't have to learn other software.
It's a bargain at £15 for a year. You can get your petrol paid if you film trails. I just love the ease of navigating to the start point. And checking the video to see if the GS will fit. There are a couple of lanes in Gloucestershire I was glad I watched before riding down. The cylinders would not have fitted in the v-shaped rock channel and getting out would have been a nightmare.
The overview page is here:
https://www.trailvidz.com/map-page/