I've played this game twice, once as a player the second as the GM.

In the first we didn't do very well with uncovering clues, and we never really got the part about the eyes or anything. I didn't enter the adventure until we arrived at stern hope anyway, so I missed alot of the foreshadowing and even investigative part.

We should have gotten clue right, but even though we heard that the one thing the demon feared was the one malus he best liked to inflict on others, at which a player asked "Pain?", and caused everyone to laugh out, forgetting about the important clue.

So when we actually met the enemy, we pretty much forgot about the clue, and instead of using it my feral guardsman with mono greatweapon simply chopped the daemon into pieces... after all the daemon had only primitive weapon (fist) so did little damage through my 12 points of damage resistance, while I did considerably more with my 2d10+6 damage...

When I Gmed it i made a point of stressing clues (as well as the general athmosphere) so the players easily cought on and when the combat came they both tried to reason with Aristarchus, spending turns getting some good interaction rolls and decent arguments, and even managed to poke out one eye with a captured cleaver (by the scum, no less). It was impossible to attribute the daemons fall to just one acolyte, so I made the combat last longer than it should have and required several tests and attempts to both break aristarchus out of his trance and attack skae's eyes.

I gave fate point award to all, and even made the cleaver semi-demonposessed, so that it got a psychic aura and a potential to hard the daemon again. The scum is holding on to it and will probably be singled out as the one who hurt him when he returns

I thought the adventure was cool, but it ended in a Total Party Kill for our group. Nobody was really playing attention to Aristarchus, aside from following his orders to the T, since he was the "commander" of the team. They didn't investigate the bodies in the hills, and when Aristarchus ordered them to bring back the wisewoman, they choose to shoot first and toss a grenade into her hut later. They fought the Ashleen and killed her in the process, and the aforementioned grenade destroyed her diary.

So they went back to the Cathedral with no clue what was about to happen. The daemon proceeded to slaughter everyone. Our Arbitrator seemed like he was close to figuring out the appeal to Aristarchus angle, but instead he just issued himself a reprimand for dereliction of duty and went to meet his fate. The two survivors stole a jury-rigged truck and took off into the desert never to be seen again.

I am planning on having the new group investigate the aftermath of the adventure after the Grey Knights have had time to pacify the area.

That goes in the books as most SNAFU'd adventure ever