@Hai-Etlik: Really? I know nothing about this stuff, but it sounds extremely odd to me. I mean, a satellite picture is just a photo, and I'm just using the photo for reference to draw the motif, and they can't claim copyright to the face of the Earth… But, I'm sure you are right. Do I have to redraw the map based on some free source then? That would give me exactly the same result for a lot more work, so I'm not really eager to do that… Is there some other way to get around it?

@Miranda: Great, thanks!