Alright, I haven't had a lot of train time lately (and the weather had been nice!)... but I took some time to make a little more progress this weekend. Here's the latest:
First, about 80% of the track had been installed (including the track over the list bridge). I added a layer of foam roadbed underneath to make it as quiet as possible, which took quite a bit of time to cut and install. You can see the double crossover in this shot:
Here's where the track ends right now... but the bridges are in place and ready to go, at least 
The yard area has track in place too, though the main loops lead off a cliff pending completion:
Back side of the layout, with siding.
Lift bridge down and locked in place.
Test car, checking the rails over the bridge
We made a template for our two mountain tunnels. Here we've traced it onto the foam:
..here's the mess part way through cutting. Jigsaw worked great, but the side effect was that (thanks to all the foam particles) I looked like a pink cherry blossom tree afterward
The kids did a rough stack of both mountains for me.
after bed time for the little humans, I went and glued the mountains together, kind of making up the top portion as I went. These will, of course, be textured and painted. The larger mountain is 38" tall at the point. I wanted it to be tall, but also (1) have space for structures of some kind and (2) Not exceed the height of the backdrop.
Track bumpers. I was pleased how well these came out & may weather them a bit:
...and, of course, after a days hard work there was an inspection of the work completed (to include the bridge capacity test, shown below)
