took the name out of the shaderfile list, deleted the previous bsp, saved, recompiled. Still nothing.
Now I can see the texture in Radiant, it loads and applys to brushes fine
http://www.creative-wiring.com/downup/errortest.jpg)
I don't have a .shader file yet - do I need one even though my map is in still early development?
Something totlally randome, perhaps its' in the way I'm compiling the map? I'm using the BSP-> Fullvis option in Radiant