On Modern Art Notes: In 2009 the Hirshhorn Museum and Sculpture Garden and architects Diller Scofidio + Renfro rolled out this concept for an event space at the Hirshhorn. Critics pounced: The museum doesn’t need it because it already has a recently modernized event space. The museum is pursuing the director’s fascination with fancy conferences at the expense of its core mission: Art. Now, almost two years after the museum initiated the project, MAN has learned that the project, expected to cost at least $7.5 million and possibly double that, has slowed to a crawl. Only one donor has come forward and the museum is distancing itself from its original “opening” date. MAN has the details.