Mesh Shadows

[RobertMurray66]

The shadows of meshes that I constuct using patches have rectanglular "holes" in them. I'm running LLW 7.5 on OS X.2.5 at present, but it was the same with X.2.3. Does anyone know what's wrong?
Bob

[danilo]

try A-hit m(merging points)
or B-try double sided polys

danilo