I ended up pulling everything apart and taking a good look at how it was designed and was able to get everything adjusted so the door would close. The gap at the left end is still not even, but it is weathertight so that's how it's going to have to be. The door operates smoothly and there's no binding or weird noises as it opens and closes so I'm calling it good. I did call Cantina to ask about the lower left pivot being installed incorrectly, but they told me my frame was out of square and sent me a box with all new hinges/pivots. Some 'solution'....