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On Mac OS X 10.7.4 I get this error Kartograph-Error: unknown shape type (1) in shapefile
when I try to load populated places by Natural Earth. I also tried to create a simple shape file with one point just to see if it loads but I get the same error. Maps with polygons or lines render fine.
It would be nice to be able to render markers and labels on the map.
Kartograph-Error: unknown shape type (1) in shapefile
A workaround for this is to use quantum gis (or something like it) and export the shp file as an csv file, and then import the csv file in karthograph.