Massively overdue for an update, I've not that much to report unfortunately!
In nor particular order, the retaining wall at Blackrock Junction has been primed, the viaduct too (though will some filler and a respray to even temporarily pass as concrete). The incline to the Crossstairs bridge has been balasted and the start of the wall made (wall on the left horizontal!).
I also painted (first attempt) the plaster tunnel mouth. The last few times upstairs I've been busy trying to clean and clear and remove stock, so I can get the overhead lighting, point motors and wiring finished!