Noel, this looks fantastic and I thank you for taking the time to do this. I don't have RailModeller and I can tell you I've been tearing my hair out all day yesterday trying to retrieve a lost password assigned to my MacBook ID which the system doesn't recognise after an Apple Update. I went to the AppStore several times to purchase the software but it won't allow me access to the account. I'm going to have to delete my old ID and create a new one.
Getting back to your drawing, it looks very good and comes close to giving me some starting point. It would be interesting to know what size of baseboard would be required for this layout - end to end - as I have a space allocated for the building. I'm getting back into modelling again, easing myself in before I take too big a jump. I appreciate your response posted here, thank you again.