My Fiance and I were playing the 1st scenario and towards the end we came across a room with a yellow impassible border (attic stairs and attic). I did not see any other way into the room at the time, and the only other door was against the wall of another room. Because of this we treated the yellow border as if it were a normal border. (Yellow borders are not allowed to be passed through.) Did we miss something / do something wrong? I didn't see any more explore tokens but perhaps we missed a secret passage or something? (we did solve both the Lock puzzle and picture puzzle).
Yellow solid borders and white solid borders are normal borders and can be passed.
Yellow dashed border and white dashed borders are impassible.
RRG Pg 5
and RRG Pg 10