Hi crydee, it looks like a bug but it is probably caused by an edge being messed up somewhere in one of those surfaces, something like a surface has a trimming boundary in it that has 2 of its own edges joined together or something like that. Something along those lines could possibly interfere with the mechanisms that build a sheet of connected surfaces by traversing edge connections.

I'll examine this more closely so that I can find out which surface in particular has the problem in it and then I should be able to repair it.

- Michael