LONDON — On a crowded shelf in Saul Nash’s crowded studio, a kitschy little trophy takes pride of place. He won it for his voguing at the Technicolour Kiki Ball last year. Usually, he walks for the House of Revlon, one of the legendary houses of the main ball scene. The Kiki scene is younger and Nash participated as a “007,” which means he isn’t affiliated with a Kiki house. He earned his prize by walking the “old way.” Anyone…