I was setting up terrain for two MRS Logistica lines in Brazil and .hgt files were the only
thing I could find. And you are right, not very good quality, 1 meter resolution if I
remember correctly. One thing I have not looked at is whether you could use Virtual
Terrain Builder to convert ArcGIS files, which you can get from the USGS site to
create .hgt files. You can use it to convert to the format required by DEMEX. And
you are correct, the version of DEMEX we have was set up to enable loading into a
Win-7/10 environment and you do have to have the purchased key. TSM is now
available free and it would be nice if DEMEX was also free but -------.