using 3.1 .gpx generated when exported it appears as a broken line

[nordlicht]

That is it would seem that what I see on the screen is different from reality

No, it's different from what you expect.

If the positionlist is displayed as a route the continuous line following the trails and roads between the routepoints is created by BRouter by generating lots of intermediate points. If you want to export this continuous line you have to convert the route to a track as described above.

Switching the positionlist from route to track switches the display mode, it does not convert the previous route to a continuous track following trails and roads. After switching to track the former routepoints in the list are interpreted as trackpoints and consecutively connected by beelines without any additional intermediate points.

Please make yourself more familiar with the difference between routes and tracks.
Your route has 63 points, the derived track has 1346 points.