Use the set move route event so the NPC walks up to the door and then after that , activate a switch. Make a new event page in the door , with your switch in the top left corner ON , and set move route for the door to Turn left , wait 4 frames , turn right , wait 4 frames , self switch A on , and make another event page with self switch A on , Make the graphic of the door fully open , and just set it to through and the bottom left hand corner , then go back to your NPC , and set move route through the door.
I think that'd work..