The dancing mask above, worn at the All-Models Exhibition Building today, is intended for a kindly character in a Balinese "wayang" dance. And here (right) is the face behind the mask Mrs. Salim herself. The masks are one of the many ideas Mrs. Salim is offering in the Indonesian trade display at the exhibition. For example, the glowing purple and pink "batik' of her costume is a distinctive textile Indonesia wants to market here. The display is to interest Australians in visiting Indonesia, and