I really enjoyed Rock Heaven, which reminded me a lot of HIS DARK MATERIALS. Maella is an eccentric, stressed-out young woman who has grown up with an incredibly vexing condition. She's already lost her older brother and father to the "curse" plus other relatives. Her constant need to be aware of the dangers of opening a door is something that preys on her. The discovery of her gift's effects don't set her free either as doormakers are hated and reviled on virtually every planet in the multiverse (or at least the first ones she encounters).
The friendship between Maella and Clarista is the heart of the book as the two are sent through the same portal into a world where they are hunted. Clarista is constant and never-ending in her support of Maella where the others in the small group are suspicious as well as hostile. Indeed, it feels like a romance as much as a deep friendship but I'm not sure if the author intends to go that direction.
I had mixed feelings regarding the character of Daniel who is a friend of both Maella as well as the bullies who prey on her. His complaints and dislike for Maella quickly wore out his welcome and I was waiting for the giant worms or tribals to kill him. Mind you, I understand how an amateur teenage boy might end up blaming the person who got them stranded halfway across the universe (or even in a parallel one).
I really love the concept behind these books as while traveling to other worlds is hardly a new concept in fantasy, the idea of having no control over it as well as it affecting mundane life like being unable to open doors is wonderfully terrifying. It's something Stephen King would come up with and makes the opening very evocative. The audience guesses it's opening to other worlds very early but Maelle's family is just perplexed and only know it as a horrible thing which happens. They don't know why, how, or what it means.
The villains in the book are also very well done. I loved the introduction of Foster as I don't recall seeing that in a book before. He's a very reasonable, personable, and heroic king beloved by his people but has a horrifying hatred of doormakers. Our protagonists are introduced to him and he's eager to help protect them when he thinks they're falsely accused, only to turn on them the instant he finds out they're actually guilty.
I like the fact this book actually has decent stakes for its young adult protagonists. They are trapped in another universe with no way to return (like SLIDERS). People also fear and hate the doormakers despite the fact Maella has done nothing wrong. The fact she has so much hatred and disgust directed at her gives her a sense of pitability that you just want to wrap her up in a blanket then give her some soup.
I could have used a bit more description of the characters and their surroundings but this is a minor complaint as the circumstances are what really benefits this book. It is an entertaining young adult work that is full of sincerity versus the usual snarky post-Whedon protagonists. I was also a little confused about the protagonists' ages as the cover indicates they're teenagers but they feel like they were written as adolescents. The book's flow isn't always smooth but the breadth of imagination which went into it makes it a stronger work than many of the indie fantasy I've read.