You ask some very sensible questions.
I'll tackle them separately, if I may, starting with the less lengthy responses !
r1owner wrote: ↑Thu Mar 10, 2022 6:19 am
I tried to email a KML file (from google maps) and use garmin drive to import it and I think it failed thus causing the infinite spinner in the trip planner.
I don't think KML files are supported by the Zumos. Basecamp will import them and they can then be exported, but the one that I tried showed up as a track, not a route. The XT will allow navigation of a track though in 4 different ways - just shown on screen, displayed underneath a route, Load a track and click Go!, Use the XT to 'Convert to Trip'.
These are described with some screen shots and an overview description here:
app.php/ZXT-P45
r1owner wrote: ↑Thu Mar 10, 2022 6:19 am
Does anyone know how basecamp calculates the route? Does it use the processor on the Zumo XT to calculate the route?
I reckon somebody must. But I am not one of them, although I have been working hard at it.
It is VERY different from the way that previous Zumos go about navigating a route (just for those that have used earlier Zumos).
It has 4 modes of calculating routes when a route is active - Faster Time, Garmin Adventurous Routing, Straight Line, Shorter Distance.
It used to be that Faster Time on both Basecamp and the Zumo gave the more predictable routing. But with the XT that seems to have changed and I am not exactly sure what it does. It is work still in progress for me.
But what I have discovered is that the XT does not select the fastest route. It seems to select routes that use (mainly) faster roads, and having found them it seems to be prepared to go a long way in order to reach them - which results in a route that can take much longer than the more obvious.
It is very hard to pin down because these later Zumos build up a profile of how you ride. I assume that means that if you always ride at 30mp on a motorway and at 100mph on a back road, then it will begin to prefer back roads to motorways. It will certainly learn your favourite routes and use those rather than what it calculates. A bit of a pain if you are trying to explore different roads !
It is also affected by traffic information. The 590 and 595 uses historic data that is coded into the maps. So certain roads are busier at 5:00pm on a weekday - so it will detour at those times when it gets the chance. (BY getting the chance, I mean if you give the route the opportunity to recalculate, it will take these trend into account.
Another source of traffic info is through your aerial - which doubles up as the power lead.
Yet another is through the drive app from your phone.
There are options to turn such things off, but I don't know if you can turn off all of them.
Anyway - if there is a faster road near(ish) to the one that I want to ride, then I will use shaping points on the road that I want to ride to try to prevent any opportunity for the XT to take me back to the faster road. In the same way that I would ifI want to avoid the M74 from Carlisle the Scottish Borders. This usually means having two shaping points on a stretch of road between two junctions - one a third of the way along from the first junction, the other two thirds of the way along. This often works. Personally, I try to avoid placing a route point anywhere near to a junction.
But I haven't got it worked out yet, so my current routing method is to adopt the above methods, and create a track of my original route. I load them both into the XT and display them both. This means that if the XT has calculated a route that is different from my original, the (black) track will become instantly noticeable. And I follow the track.
Having said that, I was out on Tuesday and managed about 100 miles through the Peak District. Got caught out by the closure of the A57 Snake Pass - which the XT's traffic info did not report - My original route (eventually) recalculated and led me back to the original black track line near LadyBower. The route worked perfectly except early on in the day when I thought I recognised the way to go, and the XT was taking me a different way. I forgot about being able to see the track as well, and ignored the satnav. I was wrong, it was right. I compared my track with the original route and it was doing everything it should have done to get me back on route.
I have altered the theme for United Kingdom so that the track shows up a little wider than the route, which reassures me that I can still see both route and track. When both are following the same course, the magenta line is edged by the distinctive black outline of the track underneath.
I've tried a few 'Shorter' distances but I can't work it out. It certainly doesn't always produces the shortest distance. So I am having trouble understanding the meaning of 'shorter'. Shorter than what ?
Adventurous routing - well you have a slider with 4 positions, and I have yet to work out what they do, other than find alternative routes.
As for the best way to transfer routes - that is a whole different essay.
People will probably / hopefully chime in with their preferred methods. I've not covered this in the Article at the top of the XT section - so I'll do the job properly and weigh up the pros and cons of the ways that I know. It will take a little lobger though.