Thanks for playing! Glad you found hidden things :) and yes, it was a trap! It would rotate you same direction each time and you need to kind of notice where and plan your movement with that in mind to pass it. We have couple of those, though two are hidden away.
We think we would 'teach' mechanic next time... something like we did with exit from the room... though not sure how many noticed transparency on the illusionary walls from certain angle... probably too subtle after all!