Created an HF2 offsetter which allows me to resample the height map you provided and reposition it into a another one so it can be rescaled to 10000 and then set into a 10240 square. That's done and running now but I need to see the results to know whether it is working or not. Its no problem for you to keep going. Its basically about 4 hrs to run from new DEM to result so we can go to the wire with changes.