It’s a bit confusing; it asks you to “draw” a route but it won’t let you actually draw a line, at least on mobile; what you have to do instead is tap two points on the map and it figures out the route for you. This can take a few seconds though and there isn’t any UI indicator that it’s thinking, so you just have to be patient.

Here is the video tutorial : https://twitter.com/rtnF14/status/1565939896183050250

Ok, it seems I'm just triggering a performance issue, which eventually causes a timeout: "operation killed by thread-priority-watchdog after 19 seconds". (I'm only seeing the straight lines I made.)

Click different points, then click on the first point (the one with a play marker) and keep clicking it until you complete the track