Dan Yonah Ben-Dror Marshall had a dream to open a community dance center in the Boston area. “With a lot of help from friends and family, he opened the Brookline Community Center for the Arts in Coolidge Corner early last year. With six studios, provisions for live music and performances, and about 100 teachers on board, he thought this one-stop shopping for dance would sell itself in no time. One year later, the center is struggling to stay afloat, and the dream could very well die on July 15.”