Spoiler warning! Players, do not read!

I really love the amount of agency players have in this module. The High House of Suffering gives you a straightforward objective and a ton of leeway in how to accomplish it, giving the players an opportunity to show off their creativity and problem-solving skills. Culkin Manor presents a difficult problem where multiple encounters can occur simultaneously in different sections of the building (potentially splitting the party), and the players have to think about what their objectives and priorities are. It can also be a very interesting battle if you use a grid for it, as enemies can move between rooms to reinforce each other, and parts of the building may be set on fire to create an environmental hazard. The Chapterhouse of the Eternal Flame brings it back to a simpler, more linear track, but it's a decent mini-dungeon.

Some notes from running it:

• The High House of Suffering is meant to be a relatively short section. If the players are spending a lot of time on it, don't be afraid to have one of the guards walk up to them while they're planning and be like, "Oy, what are you lot doin' loitering around 'ere?" and, in the course of conversation, nudge them towards the bribery option to move it along.
• When the players are bringing the girl back to Culkin Manor, consider calling for skill checks to transport her discreetly. It doesn't actually affect the outcome, of course, but if they roll well, you can nod approvingly, and if they roll poorly, you can say, "Hmm, ouch, that may have some consequences later in the mod..." and they'll probably assume that's why the manor gets attacked.
• I haven't figured out a good way to ask the players where their characters are going to be sleeping without telegraphing that they're going to be attacked in the night (because why else would I need to know that?). Experienced players will know something's up. It's no big deal, but, y'know.
• The module suggests having players spend two rounds to move between rooms in Culkin Manor. This option works well for theater of the mind; however, if you're using maps, simply moving from room to room on the grid will likely be more satisfying for players.
• If you're short on time, you can run fewer encounters in Culkin Manor to expedite the section, or replace a combat encounter with a skill challenge (e.g. "A room is on fire and you need to rescue someone or something from out of it").
• Why the heck are cultists shoving a dude into flaming armor, and why does he turn into an azer afterwards? Well, it's explained in a sidebar, but players don't get to see that, and they'll probably have no idea what's going on. I suggest allowing them an appropriate skill check to deduce the information in the sidebar, because it makes noooo sense otherwise.

Overall, the module is great and I like it.