Not often do I write to this topic, but I have to praise all the contributors. I just completed the version 2 of the Zigzag stairs. A robust GBC module that I completed in two days and a further 2 days of testing with no spills. I guess I have spent weeks on the version 1 of Zigzag stairs to no joy. I admit my eyesight and lack of muscular control may have contributed but I am quite happy with this module. Thanks!