Thanks for the kind comments. Running under the decking allows me to use Aristo 6.5 diameter curves. Essentially the main circuit has no curve tighter than radius 3, allowing the use of non LGB stock that requires a bigger radius than R1. The two sections of half circle under the decking use stainless steel track to reduce the need to crawl under for cleaning. Galvanised cable tray makes up the track bed on the elevated sections, suspended using variable shelving channel and threaded rod. This set up allows easy adjustment of gradient and camber and doesn't really require any maintenance. The downside of the layout is that in order for the line to climb up and back over itself, the gradient is about 1 in 15 at its steepest. Not a problem for short trains, but longer trains really need to be 'driven' to maintain a sensible or realistic speed on the ascent and decent. A problem probably solved if I take the plunge replace the Aristo TE control I use just now with a digital system. The plan for the next phase is to run a service line into the shed before winter sets in, then next year construct an alpine line climbing from the shed up the back fence to a terminus.