UPDATE: George Lucas said the following about Freeborn in a statement released on StarWars.com:
"Stuart was already a makeup legend when he started on Star Wars. He brought with him not only decades of experience, but boundless creative energy. His artistry and craftsmanship will live on forever in the characters he created. His Star Wars creatures may be reinterpreted in new forms by new generations, but at their heart, they continue to be what Stuart created for the original films."