I have been making my first steps, apparently being the first one to map at the island of Pantelleria. At least I see no other data except the coastline imported from somewhere.
That brings me to my first problem: The coastline has some kind of triangular inland pond that doesn't exist in reality and happens to overlap with the local castle. I can't get rid of this "pond"; every time I try to delete it, upload of the change fails. Any hints on what to do here?