When the powers behind the 2010 Tel Aviv production of Hanoch Levin’s Holocaust opera The Child Dreams sought a designer, it seemed like plain sailing to bring on the Austrian provocateur Gottfried Helnwein, distinguished alumnus of what he calls “the same academy that rejected Adolf Hitler twice — which is, of course, the biggest mistake that any university has ever made in history.” As Helnwein lurks watchfully backstage in signature shades and head scarf, his qualifications to assay the great theme of betrayed innocence might at first seem dubious. You’d sooner expect to see this guy gathering groupies for a catastrophic jaunt back to the tour bus. But his vision is revealed as grand and arresting, especially when he balks at casting a young woman in the role of the child. And while the opera nonetheless soars with its acrobatic choreography of refugee displacement, this documentary about it suffers some dramatic slackness from the inevitable drawing board tedium of performance preparation. There’s too much throat clearing, telling us how the late playwright Levin, reportedly “not scared of not being liked,” would have been simpatico with this famed portraitist of wounded kids. The film rightly admires Helnwein’s work and serves it best when just showing it.