Hi Paul, do you mean if you load the same model into the previous beta you don't see the same kind of thing there?

If so is it possible for you to send the model to me, either post it here or e-mail it to me at moi@moi3d.com if you want to keep it private. That will give ma a chance to see what's going on.

But often times if you get some weird looking polygons that appear to sort of leak out past the regular boundaries of your object, that can be a side effect of messed up trimming boundaries, for example trimming boundaries that have self-intersecting loops in them make it so there is not a clear inside and outside to the boundary and that can confuse the display mesher.

The outside area is probably part of the "underlying surface" - if you use Edit > Separate on your object and then turn on control points you'll see how the underlying surfaces are often larger than the current visible area, and if the trimming boundaries are messed up it's possible for the display mesh to get out into some other parts of that underlying surface.

I'm not entirely sure if that's what's happening in your case or not though - it's pretty hard for me to guess what's going on without having a model file to test with.

- Michael