Awesome video and awesome layout! Nothing worse than waiting for someone to quit yabbering on for 5 minutes when you just want to see the layout.
Could you/did you go into detail about the mountains you did along the basement wall? I'm more or less trying to accomplish the same exact thing on my layout. It looks like cardboard lattice and plaster cloth?
Yep, that's exactly what I did. The below image shows basically every step from beginning to end. Starts with simple cardboard strip lattice. I then covered the entire thing with plaster cloth and on top of the plaster cloth I smoothed on joint compound; sculptamold or plaster would work just as well. Once it dries I decide where I want to add and carve some rocks made of plaster. I throw on some brown paint and add various colors of turfs, bushes, and trees. I still have to go back and add some more coloring to the rocks, add more trees and small details and such.