Hi Gordon, yes like dferyance writes above the "won't follow it" problem is a display artifact where there the display mesh isn't getting quite enough triangles in that area to make it look smooth. The actual surface is curved there and fine, it's just a display thing. The display is oriented around doing things quickly and so there are various compromises in it like this one. So that's just something to ignore. That particular display glitch will tend to happen on objects that are long but only shallowly curved like you have there.

For the gaps thing yes that sounds like it might be a different thing and if you can post your .3dm file that would help to answer that part.

- Michael