Hi, there is a new version (8.11.2017), https://github.com/FSofTlpz/Garmin-DEM-Build/blob/master/BuildDEMFile/bin/Bu.... This version should be assume less memory. Reading HGT's should be faster. It seems, --lastcolstd isn't more necessary (?). By the way, the programm runs also with linux mint 18.2 and mono. Main options: -d, --dem=arg name of DEM-file, (e.g. 70210001.DEM) --hgtpath=arg directory for HGT's (zipped or not) --tre=arg name of TRE-file (e.g. 70210001.TRE) -o, --dlon=arg distance between DEM-Point (multiple usage for more zoomlevels) --usedummydata=arg use 'without-value' (0x8000), if one or more HGT's not present --lastcolstd=arg last subtile column has ever a width of 64 (need a little bit more memory on disk) -O, --overwrite=arg overwrite existing destination files or not -f, --foot=arg DEM data in foot or meter Frank --- Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. https://www.avast.com/antivirus