"Dog Run" is an authentic-looking movie, a warts-and-all depiction of the squatters, drug addicts and homeless kids fending for themselves on the streets of New York. But director/co-scripter D. Ze'ev Gilad is on shakier ground when he tries to dramatize the situation. As Eddie and Miles become involved with two women, drug addict Tara (Lisa Ristorucci) and college student Rachel (Elizabeth Horsburgh), the film becomes less realistic and more contrived. The relationship between Miles and Rachel is especially unbelievable, a fake "West Side Story" for the modern day. Starring Brian Marc, Craig DuPlessis and Lisa Ristorucci. Directed by D. Ze'ev Gilad. Written by Brian Marc and D. Ze'ev Gilad. Produced by Jeffrey Feldman, Brian Marc and D. Ze'ev Gilad. An Arrow release. Drama. Unrated. Running time: 104 min.