Pretty Problems

Class divisions that assume macrocosmic significance in Ruben Östlund’s “Triangle of Sadness” remain microcosmically scaled in “Pretty Problems,” another cleverly discomfiting, festival-blessed comedy hitting theaters on Oct. 13. Kestrin Pantera’s third directorial feature, which won the Audience Award at SXSW, also places a less-advantaged young couple in an enclave of…