Does anyone have a description of AL's book "the big book of granny"?

All i can find is the cover page, and a few police statements.

This was never fully released. I'm assuming that this is what you are talking about when you say police statements but I'll put it here for reference.

This is a description of the book and the cover page. The illustration on the cover was drawn by a co-author and not Lanza.
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This blog post explains that some of characters in the story seem to be named after characters on Dora the Explorer. I never watched this show so I was unaware of the connection and thought that was interesting and worth mentioning here.
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This is a statement from the co-author's mother. There isn't much about the book here but she says that Lanza and her son were friends and spent time together outside of school, including visiting each other's houses. She says Lanza seemed normal.
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This is a statement from the co-author. It explains that he is under supervision and living in a group residence and another report clarifies that he has a mental illness, though they couldn't determine whether it was involuntary confinement or a community based supported residence. In this statement, he contradicts what his mother told the police, saying that they never saw each other outside of school. He says that Lanza was weird.
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This is what the additional report says about the content and significance of The Big Book of Granny.

Office of the Child Advocate Report wrote:

Most striking during this period of AL’s life is the publication and submission of “The Big Book of Granny.” There is intense violence featured in this book, and authors conclude that it was not the sort of creation that most children would even know to invent. Mental health professionals contributing to this report determined that the content of “The Big Book of Granny” can only be described as extremely abhorrent and, if it had been carefully reviewed by school staff, it would have suggested the need for a referral to a child psychiatrist or other mental health professional for evaluation. An appropriate evaluation would have required extended discussion with the child about what the book meant and how it came to be written by encouraging extensive elaboration about what the text revealed regarding the child’s thoughts and social-emotional processing.

Here, “The Big Book of Granny” suggests that while in many ways AL appeared to be positively developing, by the age of ten, on some level, he was deeply troubled by feelings of rage, hate, and (at least unconscious) murderous impulses. While many children, and especially boys, of this age contend with anger and violent impulses in their play and creative productions, “The Big Book of Granny” stands out, to mental health professionals, as a text marked by extreme thoughts of violence that should have signified a need for intervention and evaluation.

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Additionally, authors strongly caution that nothing in these findings would predict that AL was likely to commit mass murder, even if a better connection had been made between the writing of “The Big Book of Granny” and a need for mental health evaluation and intervention. What the book does tend to show is a boy who is struggling with disturbing thoughts of extreme violence that seem to have poured out in the form of stories and visual images of a caregiver and child-like character who are alternately victimized by and victimizers of each other. On the surface AL appeared placid (or “neutral” as one teacher later put it), but this book is a clear indication of severe emotional conflict that AL as a 10 year old could not be expected to understand or resolve without help from adults and professionals.

This seems to be everything available about the book.

Okay that's cool. Thanks.
Kind of worries me because when I was little I made absurdly violent comics.