So I'm working (or trying to work) with RRTrack tonight. The squares are 12", the large radius sections are O72, and the smaller curves are O54. But things do not line up correctly. I verified that 16 O72 curves make a 6' circle, and the same all O72 switches or 072 Y switches. Everything makes a 6' circle with 16 pieces. So everything should be interchangable, right? Wrong! Look at the attached screen grab and someone please tell me where I went wrong.