You need to put them in the shaders folder.

Having said that you only really need the topcoat shader as you can choose a colour or texture for your primitive/figure through the surfaces tabs(under diffuse/colour) and then apply the top coat again making sure you have highlighted the figure/primitive in the panel above the shaders tabs as well as in the scene tab.

The topcoat is fantastic on floors in DS.Gives a floor that ballroom shine.