As Zipper: Coney Island’s Last Wild Ride tells it, Brooklyn’s favorite amusement park has been a place of gleeful disorder that outside interests have attempted to encroach upon for pretty much its entire existence. Put together with a bit more flair than the average shoestring documentary, Amy Nicholson’s love letter to the rapidly changing neighborhood attempts to mirror the colorful, working class, and endearingly rough-around-the-edges spirit of its subject. Nicholson pulls this off, but her clear affection for the sights and personalities that make Coney Island what it is gets in the way of a hard-hitting investigation of why it hasn’t maintained its luster. As a result, the film is more effective as a loving send-off than an insightful look at the so-called “tides of progress” that have led to Coney Island’s slow decline. (In the film’s most entertaining sequence, Nicholson bridges that gap by cutting between first-person footage of at least a dozen different people on the eponymous ride and interviews with the Zipper’s manufacturers and operators.) Zipper doesn’t just point the finger at Mayor Bloomberg, developer Joe Sitt, or anyone else involved in plans to rezone Coney Island and allow corporate outsiders to repurpose the entire neighborhood. Instead, Nicholson points out that the unstable financial foundation it’s been resting on for decades has made it increasingly vulnerable to such attacks. The film finally has no choice but to throw up its hands and conclude it was fun while it lasted.