Was very happy to discover Railmodeller Pro for Mac. It is excellent. I have just reverse engineered our layout ready for expansion to the final track phase (i.e. the green track is yet to be laid but all the other track is now laid). I love the flexitrack manipulation features on this software. It was so easy to learn. Our layout 'Kingsbridge' is constructed mainly using Peco streamline flexitrack and Peco 00 gauge stream line code 100 points.