Despite not being familiar with the original Pickman story, the story for this one-shot was not difficult to follow. Everything was laid out in a clear manner, and made everything easy to follow. The hand outs were neat, and adds a level of immersion.
I would recommend reading through the story a few times to make sure that you know where all the dice rolls are.
Overall I would definitely recommend this one-shot. It has an interesting premise, is neatly organized, and well put together.
[5 of 5 Stars!]