4 stars. The layout and some information being buried in the text hurt the rating. A DM may want to hightlight the number of evil mages in part 2. Some of the DC are low according to my players. I think the DC should be not less than 15 for tier 4 module. This does not include spell dc from monsters.
We all enjoyed the advancing/delaying idea. The Madness Chart on page 5 was fun and will really affect game play if the players go along with the idea. They were a little confused with the four choices. DMs will need to point out how little the information the module gives you. It took me some time to get my players to understand, the setup for Part 2 was a quick overview lacking details.
Due to time we did not finish all of part 2. So DMs need to watch the clock on Part 1.
[4 of 5 Stars!]