... Martin Wynne Dear all, I'm in trouble with the words again. Following the consensus here I have settled on "irregular" for the non-regular diamond-crossings (although I'm still worried that it will mean "wrong" for some users and lead to a lot of support requests). In such an irregular diamond-crossing the two half-diamonds differ. One of them has the V-crossing angle shorter than the K-crossing angle, with the result that the diagonal-road radius is positive: 2_131601_530000002.png The other half-diamond has the V-crossing angle flatter than the K-crossing angle, with the result that the diagonal-road radius is negative: 2_131601_520000001.png I need some words to describe these two different cases. To describe them as "positive" and "negative" would lead to confusion, because in each case the main-road curving radius could be positive or negative at the same time. (Shown straight here for clarity, and somewhat exaggerated.) Possible words are "diverging/converging" ...