I recently went to a tech conference, and decided to run the Asmodean Knot from book 2 as a one-shot. I'm currently running it for my group, so I already had everything fresh in my mind as well as everything set up in Roll20. I figured I'd tell everyone what I did, just in case anyone else is thinking about doing this themselves in the future (or just plopping the dungeon into another game, which I heartily recommend).
What I changed
The first thing I had to change, of course, was the opening. I made it more generic, since it didn't really matter where the players were based.
The new opening:
One day, you're all called to your local Pathfinder lodge. A few days ago, a crowd of new adventurers took on a contract to clear out the long abandoned mansion of a crazed mage, Vheed. The town had been on the verge of taking him out on their own due to rumors of gruesome experiments, but found he was missing. Uncertain as to what to do, they opted to leave the mansion alone, worried burning it down might unleash some magics they were unprepared to deal with.
A band of goblins had taken up residence, so the Lodge was tasked with clearing them out. The adventurers did so easily, but then came upon the entrance to what appears to be a pocket dimension. Stating that they "weren't being paid nearly enough", they returned and asked the task be finished by someone else.
I skipped over the trip to the mansion and getting to the dungeon, dropping them in the first room right off the bat.
As for Sian, I changed her to merely be someone who heard of the fleeing adventurers and is determined to find what the dungeon holds before anyone else. Because of this, though, I decided that she could possibly be talked into joining the party, though she would still try to get the drop on them. It would take some fairly high rolls, but I've learned to never underestimate the ability of players to sell crazy plans.
Her arrival time means that the first adventurers did not see a body, allowing the players to deduce that they're not alone in this dungeon.
I also dropped everyone's level to four since so many people showed up, and spare characters were available if anyone bought it. Also, the sheets I found only had the levels one, four, and seven, and I didn't want to spend time leveling up on PDFs.
How'd it go?
It went really well! The players all enjoyed it, and most of our issues were due to limited table space and the dungeon being a bit too big for one play session. Because they knew they could just grab a new character if they died, they were extremely creative when it came to solving the puzzles.
What I'd do differently
I'd probably rework the dungeon to be shorter. There are a few bits that could be removed without hurting the overall feel, like some acrobatic puzzles and a rather large maze. There's also a prison area where I feel like everyone would choose to avoid the encounter, it may just be better to leave it out. This would mean moving the item found there to another area of the dungeon, but there's more than a few places to stash it. Maybe Sian found it, or maybe Jabe could be wielding it.
While my players opted to not get the reward from Livia, I think I'd have to change what she gives them. Instead of six answers (which is of little importance in a one-shot), I'd probably give out some potions of lesser restoration. In The Council of Thieves, the players start out with four, so I feel like that would be a fair swap.