I've got the slope section (down to the lower level terminus station) temporarily in place and tested that a train can run up it. I used a small loco as it's not long enough for even a four car train. The NGS hunslet ran up and down okay, so fingers crossed for a complete train, otherwise some drastic re-think and track bed surgery will be required. The slope section is effectively the station throat and will need to be removable as it will contain the points.
It has been raining so I can't do any sawing (as I like to do it outside to prevent huge amounts of sawdust in the shed). And, now that it has stopped raining and the sun has come out, it's phenomenally windy so I've spent a little time jiggling buildings and structures in to place to check on positioning and space, and to be able to mark up and cut the station board to fit. The room available for the terminus platforms is quite restricted and will need quite severe compression - but then I knew that compromise and compression would be necessary and the layout is only a representation and they will be hidden under the train shed.
Here's a couple of snaps: