Pro/Engineer has a ton of ways to get geometry information from one model to another such as publishing your geometry, or copy from other model, one we are covering today is a quick (I call cheating) way to get model geometry from one model to another, I have seen it used to copy surface references from a part into a model to build a tool for making the part. if you assemble your original model into an assembly then assemble a blank part that will become your tool you can 'activate' the blank part and copy surfaces from the original model into you "tool". One downfall to this method is that the assembly must be present to make changes to the reference surfaces, where as copy from other model method all you need is the part you are copying from. Anyway one thing that must be set in your config.pro to allow you to copy surfaces while in an assembly is "default_ext_ref_scope all" this sets the scope of what references you can copy or use. Caution! this ties your model to the assembly forever so I would use this only in special situations and make sure to set it back to "none" when you are done or you will end up in Circular Reference Hell.