I asked this question else where, in a little of a hurry. When you want to apply a shader at render time, do you have to apply PreRender MEL code ? I only want to assign a post render shader for the MEL code, which I have done for PostRender MEL, but when I remove the script my old shader is completely removed, although I have up to this point reloaded the scene, I still want to know why this is happening when the script is removed from PostRender ?
select -r [object]; hyperShade -assign checker1 [object:shape]