Hi Minko, thanks for the link. I tried the biking map. This map seems to avoid the problem. They don't set the extra flag that is causing trouble, that means the DEM data doesn't contain voids (or invalid/unknown heights), and they don't use irregular bounds so they don't have a need to mark height values as "invalid" or "unknown" . I assume that they have interpolated the voids in the hgt file (if any). They also seem to prefer splits at 1/2 degrees for lat and lon while also aligning the upper left corner to multiples of dem-dist which is the common 3312. So, maybe that's they way to go. Gerd ________________________________________ Von: mkgmap-dev <mkgmap-dev-bounces@lists.mkgmap.org.uk> im Auftrag von lig fietser <ligfietser@hotmail.com> Gesendet: Sonntag, 4. Februar 2018 11:13 An: Development list for mkgmap Betreff: Re: [mkgmap-dev] My findings about the crash in MapSource Hi Gerd, Maybe you can have a look here: http://openmaps.eu/garmindownload _______________________________________________ mkgmap-dev mailing list mkgmap-dev@lists.mkgmap.org.uk http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev