The canyon is taking shape with the addition of lots of foam.  Not all of the layers are solid foam as I used ribs of foam in the middle of certain levels to hold up higher layers of foam while reducing weight.

This view of the developing module was taken with it set at the standard 50" height.  The lower shelf is installed and some initial layers of foam installed to provide a base for building up the canyon. 

These photos show the initial framework for the module.  Because of the plan to include a canyon, I had to prepare a box structure to allow for the module to have a split down the middle.