We played this with 5e, and just two experienced players, a mage and a paladin.
Overall the adventure was a blast to play, old-school treasure hunter style. Since you get free spells via cantrips and rituals in 5e with a mage, they were able to avoid many of the traps with Mage Hand and continuous use of unseen servants. As Bryce (whatever his real name may be) says, it is very slow: there is nothing that punishes the players for idling time. Once they realised this, they took full advantage of it. They took about three weeks to throughly loot the tower, to the point where they bought vials for the acid from the acid pool with the returns of their first round of loot. Some specific tactics enabled by the lack of time pressure:
(SPOILERS follow): Play with a ghost for your soul to remove a force field? F*ck that, we'll just chisel our way in from the floor below. So what if it costs a day. Tired of playing around with the force fields in the treasure chamber? F*ck THAT, let's hire a dwarven demolition team and tunnel down from above through several feet of solid rock. I thought about the dwarves getting greedy and trying to overwhelm them in the face of all that gold, but then this was a fair solution to tackle the problem, so no. They however did get trailed back to the tower by a mage with a bunch of henchmen whom they sold the more interesting loot to, and had to barricade and negotiate their way out of that. Since they could not carry enough to make off with all the treasure, they also had to leave behind about 28,000 cp, the rest of the acid and the books for them.
Some of the scenes are hilarious fun, like the one where the mage licked the microscope slides clean. Or the attacking blood -- as it does only one point of damage, it does nearly not hurt at all, its more of a weird itching. Man, were they scared of being infected. Preventive cure disease by the Paladin, just to be save. Or the brain maggot: the Paladin tried to snort acid up his nose to get it out again. He had to go to his deity's temple in the next bigger town, and after trying everything form cure wounds to cure disease (lesser restoration) to remove curse, they had to resort to splitting his skull open, fry the damn thing with sacred flames, and then revivify him. I also ruled that they could find a book in the library that explains its ecology with enough search or a good library use roll. It seems pretty shitty to give the players a whole library worth of monster books, and then all of them are useless.
In playing, I found there are a few incongruent things in the tower layout: firstly, where does the blood come from that trickles through the keyhole and washes down when you crash the door? It is not in the chamber beyond, or the mage would be knee deep in blood, and the circle long dissolved? I ruled that it is magically created by the keyhole/door, there is no reservoir; still sloppy. Second, how is the door locked from the inside, if the former head servant made off with all the spell books (which my players figured out from the diary and an added empty "strongbox" in the library area)? Third, what is beneath the entry floor and above the basement? The stairs to the entry floor lead "from the ground level up", and given the length of the stairs on the map, even if they were a lot flatter than the artists interpretation on the cover, they should go up at least a floor of 15-20 feet. But there is no such floor in the tower. I decided it is just solid rock, to protect against ramming.
I think three things would make the maps a lot more usable: (1) indication in which direction doors open. This makes a hell of a difference when you are trying to bar or spike a door. (2) Indication how thick walls and floors are. (3) A cross section with height indication. This makes it a lot easier to judge if you can reach a ceiling, and how long it takes you to get through by force. Sure, I can make all that up, based on the overall size of the tower, and I did. But to parrot Bryce, this is the writer's job. It costs next to no extra effort to use doors with an indication to where they open, and a cross section would have easily exposed the logical construction flaws. These are things that /do/ come up in play, they are not useless backstory.
