Terraform Export and Import Disagree on Values

To test:

Load a New Mission
Create a terrain
Make sure your Ork is standing on the terrain, and press Alt C and center the camera view on the Ork.
Enter the Terrain Terraform Editor
Select File -> Export Terraform Bitmap
On the right selection Operation -> Bitmap
Click Choose and navigate to the terrain heightmap you just saved.
Click Apply.

Camera resets, so you'll have to find your Ork... But where did he go? Fly around under the terrain, you'll find him.

What's happening? It would seem that the mapping of elevation to color value is different between the exporter and what the importer expects. The RGB value difference between elevations in the heightmap exported by Torque don't accurately represent the elevation changes in the terrain in Torque. At least not by what the importer expects when reading those values on import.

Another example is to start with a heightmap you've made externally and then export it with Torque. Compare the color values before and after...

Any suggestions on how to fix this or at least work around it? I have a terrain that I originally started out with a heightmap for, did some work on it in Torque, but now I need to shift everything South. I can export it, and edit it, but when I re-import it, the vertical scale is off.