Zooming does work correctly. I was just confused first time when I moved zoomed out as far as possible for the selected map, and still I saw a lot of map area outside that. But now I understand that this is the auto-loaded adjacent map. I notice that the max zoom out is defined by the selected map. So even though there are auto-loaded maps covering a larger area, I can't zoom out to get the complete map area within the screen area. Which makes sense, since the selected map wouldn't have been displayed in that case.
However, allowing to zoom further out than defined by the selected map, would been useful in the case you have for example a city map with detailed street zoom level, and another map covering a larger area around the city (including the city). In those cases it could have been useful to zoom even further out than what the city map defines. This could be expanded to an even larger map covering the whole country. So that would allow you to zoom out to see the whole country, then zooming into a city to see the detailed streets. I have maps like that, but have to manually select the country map to be able to zoom out to see the whole country. Then I need to manually switch to the city map if I want to zoom into the detailed city streets. Which is ok. I can see it would be challenging to swicth maps like that automatically when maps are overlapping and how to decide the priority of maps.
So everything is fine, Menion.