A Chilean girl and a German teenage skier meet in the snow-covered Andes and quickly get along. So what can go wrong?! Well, for starters, the German skier can disappear without a trace. The hills may be alive with the sound of music, but in The Meltdown (El Deshielo) , the mountains are alive with potential horror that is not immediately obvious. The sophomore directorial feature of Chilean actress Manuela Martelli  ( God Will Not Help ,  The Future ) explores hidden truths and trauma on the personal, family and bigger political levels. The movie, world premiering in the Cannes Film Festival’s  Un Certain Regard  section, marks Martelli’s first writer-director effort in the Official Selection. Her Chile ‘76 had debuted in the Cannes Directors’ Fortnight. Maya O’Rourke plays young protagonist Inés, Maia Rae Domagala is skier Hanna, 15, and Saskia Rosendahl plays her mother. “Chile, 1992.…