Nights run long at Full Frame—into the next day, in fact. Thursday evening ended on Friday morning, spanning midnight with the disappointing biographical documentary Kurt Cobain: Montage of Heck. This is the first film bio authorized by Cobain’s family since his 1994 suicide, using lots of never-before-seen home movies and footage of his personal notebooks, so I went in with high expectations for an inside look at the Nirvana frontman’s life and mind. Immediately, however, I found myself mentally editing its 132-minute sprawl. This feels like a first cut rather than “this generation’s The Wall,” as director Brett Morgen has hyped it.

This is an ambitious, high-profile project. Universal Pictures and HBO Documentary films are two of the four production companies involved. Morgen has been working on it since 2007, when Cobain’s wife—musician Courtney Love—approached him with the idea. Her fingerprints seem to be all over the final product and, although Love is merely thanked in the credits, her daughter Frances Bean Cobain (now 24 years old, and a successful visual artist) is a co-executive producer. For at least the part covering the second half of Cobain’s 27-year lifespan, Montage of Heck ends up being more of a family’s public telling of its own official version of the story than a frank portrait of an already troubled superstar doubly troubled by his own stardom.

Talking-head interviews with Cobain’s parents and stepmother, his first girlfriend and Love offer only occasional insight. All of these players sound defensive, as if they are testifying in their own defense at a trial to determine who gets what chunk of the responsibility for Cobain’s misery and suicide. Love even looks dressed up for court—painted, coiffed, in a crisp outfit, and chain-smoking like a film noir widow on the witness stand. Although she can be forgiven some guardedness considering the intense publicity she and Cobain endured, Love doesn’t approach the unrehearsed sincerity of Nirvana bassist Krist Novoselic in interviews. Drummer and vocalist Dave Grohl is noticeably absent.

The film follows the arc of Cobain’s life, from home movies of an affectionate, tow-headed toddler, through the trauma of his parents’ divorce and the agony of bouncing around from household to household as a teen, to his entry into the musician’s life including meteoric success and heroin abuse.

Throughout, the film is overstuffed with concert footage that, instead of revealing how innovative Nirvana’s sound and message were, as well as the role that Cobain’s childhood trauma played in it, renders the band generic and unremarkable. Morgen (perhaps justifiably so) assumes we know why they were so great, choosing to show us their phenomenon rather than their significance. We never get to see them perform an entire song, but we get to see all their equipment-destroying antics.

What insight Montage of Heck offers comes through Cobain’s archive of spiral notebooks and his intimate home video with Love and their daughter, Frances. That video provides the most interesting—and harrowing—sections of the film. You see two really smart junkies bingeing in their apartment, insulating themselves from the world as best they can. Somehow, a lot of hilarious and loving moments come across, even if they seem on a knife’s edge. It’s touching and dread-filled to see Love clamber onto Cobain’s back while he destroys a toy guitar on the floor.

Morgen presents Love’s pregnancy and the media storm around it as the turning point in Cobain’s tragic narrative. The press—most notably a critical 1992 Vanity Fair article—pumped out constant assertions that Love was using heroin during pregnancy and that Frances was born addicted to heroin or methadone. Love admits to using heroin once when she was pregnant but before she actually knew she was pregnant. She says the rest of the reports were lies.

Nonetheless, the intense publicity led to a Los Angeles County Department of Children’s Services court battle before Seattle child-welfare agents took infant Frances from the couple for about a month. Comparing video before and after the ordeal, this seemed to permanently break something inside Cobain. Venomous writing to reporters appears in the notebooks, and his time onscreen with baby Frances is both loving and somehow fatalistic, like he’s saying a long goodbye to her. It’s heartbreaking to watch someone in such pain make a baby giggle.

In conveying the evolution of that pain, Morgen’s animation of Cobain’s notebooks is alternately illuminating and problematic. When he works with the writing—feeding lyrics to you line by line, for instance, as a song plays—the animation serves as a riveting, dramatic reading. But Morgen’s animation of Cobain’s drawings is grossly over-dramatized. The monsters, demons, fetuses, rednecks and other haunting characters in Cobain’s psychic life exaggeratedly scream at and massacre each other. Red magic marker blood spatters the screen a la Gerald Scarfe’s visual effects for Pink Floyd—The Wall. It’s not that the imagery is off-putting; it’s that the huge liberties that the animators take are exactly the kind of misinterpretation of Cobain’s anger that the film tells us drove him into solitude and self-abuse.

Instead of illustrating the troubled space of Cobain’s psyche, the animated drawings come across as corpse-feeding on the filmmaker’s part. I saw so much more of Cobain’s desperation in his listings of possible band names and in itemizations of expenses like gasoline and the light bill against his scant janitorial income before hitting it big. I didn’t need to see ballpoint-pen monsters ripping other monsters to bloody bits to know that Cobain was troubled.

Another disappointment was the way Cobain’s death was handled. The chronology crawls right up to it, and then the screen goes dark with Morgen giving us the fact of Cobain’s suicide in two sentences. His parents and wife, and even Novoselic don’t talk about it. We don’t see Cobain’s last notebook entry, or see the last footage of him and his daughter together. Essentially, Morgen shrugs and walks away.

While one can argue that a discussion of a subject’s death is just a biodoc convention, the public spectacle of Cobain’s suicide seems to require it here, particularly after over two hours of overwrought setup. Perhaps my desire to hear Love, Novoselic and Cobain’s family eulogize him is symptomatic of the media and fan predation that cost Cobain everything. But I’m not inclined to give Morgen the benefit of the doubt and say that he chose subtlety over spectacle, considering he didn’t make that choice anywhere else in the film.

More plausibly, Love didn’t want anyone to talk about it, and Morgen didn’t want to push. It’s unknowable, with this theory, as to whether Love might be protecting herself or her daughter. What’s evident is that Montage of Heck has flaws in the way it delivers its trickle of new information about Kurt Cobain, and deeper flaws in its avoidance of the hardest and most interesting truths about him.