advanced rendering for AutoCAD
There is no gamma adjustment. I assume this is supposed to be a very dark blue? If so, try using it in context (applied to an object in the scene) and see how the renderer does. Otherwise it may require lightening in PhotoShop or eq.
Looks like there's a problem with the image file-- it's probably color mapped and not being handled properly by nXt. If I convert the .tif file to a .jpg it appears to work properly. (It does not work, for some reason, if I convert it to a .png.) Not sure exactly what's up here-- but I'll take a closer look when I get a chance. In the mean time, either convert the file to .jpg or use the color coordinates directly in the interface.