Some of the files for areas you would need to cover in just a few weeks get to be a bit large - couple of Gig - for trying to download from the roadside coffee shop. Even central and south America is nearly 1 G and anyway, it is useful to have it all loaded well before you go so you can do some familiarising and route planning.
But yes, still best to download a new file just before you go and keep the old one on your computer in case the new file is missing tiles or whatever.

Yes, renaming should work, but it doesn't always stick, but perhaps that is just because I had Europe, Americas and Australia maps on there at the same time and Garmin GPS wouldn't show the renames. Doesn't matter because they are different parts of the world so there is no ambiguity or conflict. Just makes the manage maps page look untidy. What would be nice is if OSM.nl could assign a random large number to all manually-selected maps because then renaming would probably be more reliable.

I did originally download the predefined countries but found that because the various countries required lots of tiles around the boundary that were also included in the maps for all those countries, there was conflict at times which resulted in there being NO detail in some of the shared border tiles. I still have them on the SD card, but in another folder just in case.

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Tony
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