The body and the door can change over the years due to various issues including some mentioned in Ian G's Boler's buyers guide. I just ordered a new set of Scamp
hinges for my Boler
as the brass ball had worn. This allowed the door to shift left in the upper corner and down on the left side. The new hinges should come in today. My issue does not prevent the door from staying closed though. I had to rebuild our door as the wood inside had rotten to mush from leaks
on the doors window. This caused the door to loose its original shape/contour. One way to check is to remove the the hinge pins and using 2 people hold the door in place with even spacing between the left & right recessed area. Not an easy task but you can quickly see if the the door or the body has distorted from is original shape. Once you have it held in place have someone (3 person is easier) to check around the contour of the door for any gaps or distortion as the other two hold in place. The door should not flex from top to bottom.