I've tried re adding the N press event and then deleting it again. Also tried adding the N event (into the same object it was previously I should add) but assigning different actions to it other than Next Room, but nothing seems to get rid of the problem. The new actions are executed, but the room still skips (again, only sometimes).
UPDATE: Thanks Desert Dog, you set me on the right track. I had indeed put the n key press event into another object by accident, but it didn't show up with the search script tool because it was the drag and drop Next Room action, not GML. How silly of me :/
Edited by BlueSkies, 17 April 2012 - 05:03 PM.