I am struggling with shadows out when exporting using the Technical Illustration Mode.

I have my Shadows set to (default) Contour - Not selected, and Fill Selected Black, Transparency 90%.

Sometimes the images export properly with shaded areas, and other times they whole image is shaded.  I've tried rotating the image (to get a different light source) but it doesn't work.  Attached are photos of what I'm talking about.

Any ideas?

Thanks.

Here is an example of good shading.  Highlights and shadows.

This photo is all shaded, no highlights.