Anquet have a standard response about this and I have copied it here for convenience
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You are unable to download mapping to a GPS unit. This is for two reasons.
The first is that the mapping we use is raster images (Pictures of mapping) and the GPS uses vector data (Maths representing lines) on its screen. The two formats are simply too different.
The second is that Garmin and Magellan have not released their protocols for downloading mapping to their GPS units.
We try hard to let people know that it is the routes that they can download to a GPS unit, not the mapping.
The primary use of our software is to plan routes on the familiar topographical mapping. You can then save these routes to a GPS for navigation. You can also print out the bits of mapping you need.
We would always suggest that people take some sort of paper map with them and not rely solely on their GPS unit.
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