Quote Originally Posted by Mike
I suspect that the miter limit has been exceeded at .5 pts for something that small.
Note that I have edited that shape so that it now has round joints and round caps. I'm not sure that any bevel/miter restriction would be the problem. You're right that reducing the line width to 0.25px does make the line go away ... but it doesn't give me the effect that I want. I added two control points precisely where the sandbar outline meets the island, then broke the shape at those points and discarded the small segment. With that line selected I did an Arrange > Convert Line to Shape. A stray, straight line runs down and to the left from one of former endpoints ... then Designer locks up.