Kurt Cobain documentary to screen on HBO & include previously unreleased material

"The film provides no-holds-barred access to Cobain's archives, home to his never-before-seen home movies, recordings, artwork, photography, journals, demos, personal archives and songbooks," they say. "Directed by Oscar nominee Brett Morgen and executive produced by Cobain's daughter, Frances Bean Cobain, it features dozens of Nirvana songs and performances, as well as previously unheard Cobain originals."
What these 'unheard Cobain originals' are precisely remains to be seen/heard, but understandably the prospect has fans whipped into a right old online tizzy.
Morgen was originally approached about the project in 2007 by Courtney Love, but says, "At a certain point, I started working more closely with (Kurt 'n' Courtney's daughter) Frances. We all agreed that because Courtney was a subject in the film, it would be best if she wasn't given editorial control. She hasn't seen the movie. I'm not sure she's intending to, but Courtney brought me into the world, and the film would not exist if she hadn't reached out to me."
Montage Of Heck's premiere takes place this month as part of this month's Sundance Film Festival in Utah...