Firstly, thanks for writing that for me, I appreciate it alot.

Secondly, I get the following error when I go to test it:

// Warning: rman Warning: S05001 Shadeop error: argument types clash in op _assign at pc 850 in "C:/Documents and Settings/James/My Documents/maya/projects/Trapped/renderman/box/shaders/doublesided_shader_doublesidedM_".
Shader "C:/Documents and Settings/James/My Documents/maya/projects/Trapped/renderman/box/shaders/doublesided_shader_doublesidedM_", Geometry "lidShape1". //

And it just renders the default grey.

However, when I tried it on a plane in an untitled file, it worked OK. Any ideas?

James