I have the same problem. To reproduce it, select a radial symmetry (works with 1, 3, 5, 10), and try to draw along the vertical axis. At some point, there will

I have the same problem. To reproduce it, select a radial symmetry (works with 1, 3, 5, 10), and try to draw along the vertical axis. At some point, there will be suddenly lines between the center, all of your "current points" and all of their opposite (opposite being the point symmetric to them by the center).