-disclaimer: I have not played this yet-
Style: 3/5. It's very striking to look at, but there's an awful lot of it that simply repeats. Why repeat the description for the hallways 36 times if it's the same every time? Way too much flicking backwards and forwards past a bunch of room descriptions to get to the game bits. The tangrams are cute as hell, though.
Substance: 2/5. I feel like I failed a SAN check reading this. I'm not really sure how I'd run it; there's both an enormous amount of stuff, but also not enough direction on how to interact with it as a player or GM. We just wander around hoping to pick stuff up? I wish there had been 1-6 sets of rooms with significantly more detail, rather than 36 almost-identical rooms, and a lot more GM guidance, ideally in one place.