Nice,
Thanks for the breakdown! I'm a max user so having a bit of trouble getting my head around the material setup...how did you merge the separate side/top layers into one object? Is the foam one mesh, with Multi ID material or a layered material? Also what's going on with the Vertex maps here?
I've had a bit of trouble doing this in the past with SSS materials and Corona, it doesn't play nice with multi/layered SSS materials. One thing I'm thinking is whether you could triplanar map the foam (using different bitmaps for the top/sides), that way you could keep everything contained in one single material for the SSS portion. I guess this could also be done using a composite map with different UV channels for the bitmaps?
Would you mind linking me where you got the bitmaps or if there's a possibility to purchase them? Would love to run some tests of my own.