..... 1 problem solved.... If you use a waypoint at the start and end and shaping points for all the other that cures the fixation on taking you to a waypoint
So you can navigate the route fine
Great. That confirms that your XT device is behaving just like any other modern Garmin device. So far that is two "My XT is useless and needs a significant software update" problems cured, with no software update. Just one comment, the start point A and the finish point B are always waypoints, you cannot change them to be anything else. The device needs them fixed or it cannot calculate or display any route between them.
....one (problem) remaining
OK, let's see if we can address that one, too. For this exercise I have to assume that the screens you see on your XT are the same or pretty similar to my Nav V, which I am using for the purposes of this exercise. If they are different, see if you can work out the differences and go from there. If they are totally different, we will have to think of something else. Now.....
Touch Apps
Touch Trip Planner
Touch the A to B route with no intervening waypoints
You should see a screen that looks like this:
Touch Map - Do not touch GO
You should see a screen that looks like this, with the magenta line of you route on it:
Now, be patient....
In the picture above, my gps (you can just about see the bike cursor) happened to be right at the start of the route, so I could quite happily have selected the destination as B. I am 100% confident that the route from A to B would not recalculate. I could ride it quite happily.
Now, to use your example, if I were say off the map, say two miles away, I probably wouldn’t even see the magenta line. If I selected A it would take me to the start point and then stop, which would be useless. If I touched B, it would in all probability calculate me a fresh route that would take me from my position, straight to B; a route created by the device and based on my preference settings. Useless to me again, as I want to join my pre-planned route, somewhere between A and B.
Zoom the map in and out a bit, either by using the + and - buttons or your fingers, shrinking and expanding the view. You might need to drag the map around a bit too, by hand. Find the cursor, this is where you are. Look at the map, just as if it were a paper map and work out for yourself the roads to ride to get wherever it is you want to be on the magenta line. This is the old equivalent of, "Please drive to highlighted route". Ride along the roads, towards the magenta line. The cursor will move across the map, matching your position BUT the map will NOT scroll: this is normal. As a consequence of the map not scrolling and depending on your the distance you have to ride to reach the magenta line and the number of roads (I am in London central so there are hundreds) you may have to drag the map manually as you ride along. In other words, treat the screen as it it were a simple paper map. Soon enough you will reave the magenta line, point your bike in the correct direction.....
You are still on the map screen.
Push the back button, lower left hand corner
This will bring you back to the screen you started with, which should still look like this:
Now touch GO
You will have the usual two choices A and B
Select B
Touch Start
Your pre-made route should now run just fine
Over to you.........