silverblade,
Thanks for responding.  I did some experimentation, and what is very weird is that only the settings for specularity seem to cause the problem.  If my attachment isn't too large, you can see what I mean.  There are two maps each for the top and bottom of the saucer.  One is the Aztec pattern, and the other is a block hull plate pattern.  I rendered images with only bump, specularity, and reflection, and one combined Spec-Reflection.