Making sensible routes in Colombia, SA

[SilverCycle]

Q: How do we get the Zumo XT to route primarily on reasonably direct surfaced roads, but allow dirt, motorways, tolls for short/necessary sections? We're in Colombia, South America.

Long Version:
It's our primary navigation device, and generally works pretty well. However, in Colombia it either tries endlessly to drag us onto dirt road diversions - some very loopy, or refuses to route at all if we tick "avoid dirt roads".

It has to be said, Garmin's Colombia mapping is a bit dated, although not as pitifully archaic as Panama (major highways in the capital opened in 2004 - missing). Would that be the problem? Would we be better off loading OSM maps, as we used in the no-Garmin-coverage Central American countries?

OSMAnd on my phone is working a lot better, although it can do some pretty stupid loops around - I guess - data discontinuities. In Guatemala, where phone and Garmin used OSM data, the Garmin often routed better.

XT settings I'm aware of are some avoid tick boxes, and "adventurous routing". We've tried fiddling with both...

[lkraus]

I don't see a lot of comments here about off-road riding or about riding in that area, so I'm not sure how much experienced help we can provide.

In any case, I would download and install the OSM maps, both to test the results during planning and to have another option if the real world does not match the map. Do not have both checked and active in MyMaps at the same time - that will cause strange results.

The OSM maps from openmapchest.org are updated every week or two. They are free when downloaded with a torrent client and work very well with the XT and Basecamp.

[SilverCycle]

Thanks, I'm downloading the SA maps now, albeit from Open Map Chest, which I used before.

@Ikraus "I don't see a lot of comments here about off-road riding...", shouldn't be relevant, in the sense that this issue is about avoiding unnecessary diversions onto dirt. Some destinations require us to ride dirt, and our Himalayans handle it well. If our Zumo XT was fitted to a Hayabusa and kept pulling this stunt, it wouldn't be as funny!

For sure a decently up to date map should improve some things, but I still don't understand the Zumo XT's urge to pursue so many obscure diversions.