It doesn't look like the texture images for the coin were included. The .zip seems to be missing coin_NORMAL, coin_DIRTY_VERT, and coin_AO. The coin is present but there is no CG cookie logo.
I had a similar issue when using the coins , only the textures were in the folder, but when I appended the coin object to Blender, they were not working. The material was fine but I had to load in each texture - perhaps something to do with the files being in a different folder and the paths not matching to what they were when Kent saved the file on his computer?
Either way an easy fix :)
