[@Hellion] I'm failing to remember any major omissions when it comes to the characters; Aech plays a larger role early on, so you see a bit more of his and the MC's friendship. The biggest change is that Sho is basically a completely different character; you actually see a lot more of Daito and Sho in general.

The trials are all completely different aside from the very last one and even that is actually the final part of a larger trial. In the movie the trials are largely based on knowledge of the creator and understanding his mindset. In the book all the trials are basically created based on the creators love of '80s media.