Thank you to all of you who responded with wise words of help from my last video, and I think I have now solved that issue of changing polarity. In this video I experiment with the Yamorc YD 8116 switch to control 2 MP10 point control motors to change two points using one address for changing tracks, and use bi colour LED as signals controlled by the point motors. Thanks to John from @DCCtrainautomation for the technical advice and help.