In some cases at the borders of maps - there appear grey rectangles in Basecamp and Mapsource (well do not mind Mapsource much - it's very outdated) - this only appears if using a DEM/contourline overview... Sorry as Basecamp is windows only - only windows installer/Mac OSX gmap file here: https://openmtbmap.org/mtbbayern.exe or https://openmtbmap.org/mtbbayern_macosx.7z Without contourlines the map works fine (mapsetx.tdb...) Contourlines map alone also does not work (mapsetz.tdb...) So the bug is clearly in the transparent DEM/contourlines map. Sometimes simply rendering the contourlines map again and the bug is gone... Seems to be not that common but also not that rare (maybe in 1 out of 20 maps) -- Felix Hartman - Openmtbmap.org & VeloMap.org Schusterbergweg 32/8 6020 Innsbruck Austria - Österreich