I was following a tutorial blender fast track and in the tutorial they were using texture painting with a stencil to put runes on a sword, on the tutorial when using the stencil it shewed up as a see though overlay. on mine nothing appears but I can still use the stencil? It was a lot of trial and error to get an invisible stencil in the right place! is there a known fix for this or did I miss a step? I have been over the tutorial several times with the same result.