“Christmas Eve in Miller’s Point” is a quiet gem of a film, although it runs about twenty minutes too long for what it is. However, Taormina’s affection for the material and capturing the minutiae of family life is evident, and that clear care makes for a rewarding experience, despite the length. Audiences will get the most out of it if they expect a slow, gentle, observation-based character study. The ensemble is a testament to the talent of these lesser-known actors, with particularly strong performances from Maria Dizzia and newcomer Matilda Fleming, playing a mother and teen daughter at odds.