Hi PaQ, thanks for the example - this is a display bug that can happen occasionally on "S" type curves. The curve displayer samples a point in the middle of the curve to see if the display polyline is close enough to the real curve, and for an "S" type shape it can get fooled into thinking that it is close enough when it isn't.

I should be able to tune this up a bit later on in v2.

- Michael