I have played this module as a DM with three players. I had some problems about difficulty of this scenario while playing though most of them were because of my own faults; I didn't let PCs to rest after the festival, I didn't reduce the power of the enemies as PCs were only four not three, blah blah... However, I guessed it would be hard even if my party were composed of four members. The overall difficulty is a bit high, especially since most of the encounters are in the last chapter of the scenario with no chance of rest on the way.
The major problem I am pointing is not about the scenario's difficulty, however. The first half of the scenario is consist of tourism in a mysterious, suspicious, and isolated village. Even though the villagers want to make the strangers in town believe there is nothing to see in the village, everything is somewhat wrong in some ways, and it is natural for PCs to guess that the tax collector did not escape the village and he is still at somewhere. My PCs were so excited to reveal the mysteries waiting for them.
Now the problem arises. The scenario encourages PCs to solve the mystery with Hack & Slash sword fight. After futile investigation PCs have made at day time, some cultists ambush the PCs at night and give them reason to get things rough. They even give the PCs a time limit. While PCs cannot see the response of 'innocent' villagers after questioning about the surprise attack at the last night, they just get into fight in an abandoned farm and a mystery circle in a crop yard. Moreover, every answer to their curiosity is there, so they don't need to struggle finding out what's going on. Since the friendly mayor is now mad cultist lord at night with absolute hostile attitude, PCs just have to kill him and solve every problem in the village. It is just wrong solution to such a mystery story.
