ray dream deletes materials, there's no way around it. but if your'e using p4 you can manually reset materials w/ grouping tool, save in prop folder, then edit cr2 to use maps. you must also remap uv coordinats exactly the same as before importing into rds. i recomend steve cox uv mapper. then paste original texture onto new uv map. save the new map, and done. if your'e not using p4,sorry i could not help. good luck ;-)