On her way to a glittering Dior and Vanity Fair-sponsored New York premiere of her latest film, Marion Cotillard spent a night in less- glamorous Detroit, playing slot machines. The star of the Oscar-buzzed “Rust and Bone” found herself unexpectedly staying overnight in the Motor City Wednesday when New York was hit by a snowstorm and her flight was diverted. Stranded in Detroit, she also learned her airline lost her luggage. Luckily, depending on how you look at it, her hotel there had an attached casino, so the “Inception” star tried her luck and wound up winning 49 cents on the slot machines. Thursday, she made it here for the Cinema Society screening at the Sunshine Cinema, where she walked the red carpet and then caught a flight to France for another acting gig. Her co-star Matthias Schoenaerts missed the premiere thanks to a delayed flight of his own, but made it in time for the after-party at Indochine, where guests included Emma Watson, Helena Christensen and Bruce Weber. French director Jacques Audiard’s flight was canceled.