1-I also noticed that the position of items in the map is quite inaccurate, especially if you zoom out. You have to zoom in at max in order to see a pretty accurate position. Apparently the item is not loceted at the center of its icon, but on the bottom.
2-yes it works this way. When you claim a station you have to be close to it. Then, if there is no land around, a new flag is created, and the station will be inside your new land. If there is already another land of yours in the area, that land will be upgraded, and you get the station anyway, even if it is not inside your land.
3-in My Lands you don't see all your lands, you see only the bases and the only land where you are close at.
It was not clear to me as well as I noticed in another post
4-No, they disappear only when the countdown will end.