Hi again.
I am tearing my hair out on this one.
I have been working on this project, adding new surface layers, objects, etc. Then, when I added a 14th Surface Layer, this problem cropped up.
I have been adding more and more SL's, some with displacement and no problems have come up, until this 14th layer. This layer is different in that I am projecting a noise pattern as a color mask, roughly perpendicular to the cliff faces. The texture is altitude limited to just the cliffs. But when I apply the color, I get strange displacement "spikes" as shown in the attached image, even though displacement is zero. I want projected color through the mask, nothing else.
I had read a few threads that talked about surface layers interacting with compute normal, so I tried a test by putting this layer before the compute normal, and that almost worked except that what got projected was very strange...like bright red and yellow colors even though the image was grayscale.
Please see attached image with explanations and settings.
[attach=1]