The first Manalive game, constituting the first part of the book, did not impress me very much. It was confusing and difficult. I liked the second one much better, as it has better mechanics and wraps up the plot in a pleasant way.
On the other hand, the game is still rather finicky about commands, and has huge, huge text dumps directly from the novel.
If anything, the best parts of this game are those from the novel itself.