The things I like about this mod, I really like. The things I don't enjoy are fairly easy to fix with DM empowerment.
First, what I love -
The puzzles are phenomenal, especially the ones in the crypts.
As with many of the season 8 mods, the role playing opportunities are vast and fun. I loved the way my players enteracted with Sister Joy and the Merman particularly.
Now, the things I didn't like as much -
The difficulty level for converting the wards is a little too high for tier 1 characters. When I run this again, I will probably lower the DC for the wards when the puzzle solving or persuasion (in the case of Sister Joy) has already provided a sufficent level of difficulty. When the players have worked really hard or roleplayed phenomenally, it feels a little unfair for ultimate success to come down to a very difficult role. I will probably lean towards judging how easily/or not easily they went through getting access to the wards and adjust the difficulty for converting it based on that, perhaps even having Ahghairon note that some wards might be harder to convert than others.
The other issue I have is the side quest with Umberlee. I have run this twice so far, and without fail, the players automatically go for the scimitar. Talking with other DMs that have run this, I have yet to hear of any party that gains Umberlee's aid and thereby acheive that objective.
The second time I ran it, I tried to make it more clear how diabolical and fickle Umberlee is, and yet when the religion role was so high and the scimitar appeared, while wary, they assumed that perhaps this was the help she promised. I think next time I run it I might allow an investigation or insight check or the like to try and determine that the scimitar is actually an illusion.
Both times I have run it, the party has failed to convert enough wards and failed to gain Umberlee's help. While the puzzles were a ton of fun, I hated the utter dissappointment of the players in feeling they actually achieved anything after the roles weren't good enough (even after a pretty good role for a tier 1 party).
[4 of 5 Stars!]