I found the same thing, my interpretation is:
- I would allow multiple players to have the same motif, it's not game breaking
- I have 4 players, so I hand out 5 cards each (20 cards total)
- The players roll 2d6 and draw the elements from the standard table in the room (unless they roll a 6, which points them to roll that dice again on the special table). Note that the player figures out what the element is, they don't just write "trap", they draw the loose stone which activates the poison darts.
- Write what the element is (see the example rooms around the edge of the pdf)
- The player randomly selects one of their own cards and adds their goal
- GM tries to interpret it (because it's more fun that way)
One other thing I picked up is you want to roll under your stay, but if you have help you add an extra dice and take the higher number, which I think is a mistake.
I have a session today, I'd love to give this a shot because it looks like so much fun!