Display States - Colors/Materials

I have been handed a project to create a display state for an assembly and change the colors of the parts based on a custom property.  I have the methods to create the display state on the assembly, and to iterate the tree to get the custom property value. What I lack is a command that allows me to specify display state in changing color/material.  The best I have found is the SetMaterialPropertyValues method but that only allows for differences in configurations.  I realize that I can do this quite easily with configurations, but the higher ups want display states.  The final intent is to colorize an assembly for lead times on parts.  If anyone knows the specific method im overlooking give me a hand.  Any help is appreciated.SolidworksApi macros