So, how long until the narrow gauge expands and takes over?

Aha ! I haven't been on here long, so my updates are very few so far! In fact not more than the toes on an amphiuma. Well indeed, the narrow gauge does seem to be spreading quite a lot, and there is the whole question of the "high level" baseboard, aka O14 micro layout. I'd quite like to go for a bit of 3D as far as the track plan goes, perhaps disappearing into a mine tunnel at the "throat" of the board, and climbing through various levels, appearing at various points. I remember seeing a photo of a NG micro layout which was a pit into which the track descended in ever decreasing concentric circles - perhaps something like that but going up rather than down, and not all on view?

It is an excellent model. Your weathering skills put mine to shame. I like the way you get the the changes in the scenery so seemlessly.

That's very kind. I must say it was a bit daunting to hack into the scenery to lay the narrow gauge track ! I used a Dremel with a cutting disk to cut through the modrock cleanly, but of course that covered everything with dust desppite the hoover nozzle nearby. So re-doing the scenic treatment around the new track was important so that it looked as though it had always been there. But I have found that the more times you add different textures and colours, and remove bits and add bits, the more natural variety you get, random just like in real life! Also the grass benefits from subsequent applications with spray glue or matt varnish as the adhesive.