What does the "2 degree" error mean in Contours>Edit Extensions when I click on the Check Problems button in Studio?

A 2 degree is a corner point (red node) that splits a contour. In other words, it's when two contour curves meet at a node in a very straight link. If receiving this error message, join the contour at the problematic point (i.e. remove the vertex) or move the vertex a little so the joining line is not exactly straight. Then, click on the Check Problems button again to see if the error has been fixed.