IN a vast, unheated room overlooking Cooper Square in the East Village, Guy Wasko tried to shake off the start-up jitters. It was late March, less than three weeks before the biggest day of his professional life, and there was still so much to do. A financial backer was wavering. The music was a big question mark: was it the right flavor for the neighborhood, funky enough, soulful enough? What about his hospitality team? The members had to be trained, the signs had to be right, the branding had to pop.