Howdy, Since, through making a template, it appears that the trailer body has sagged, (straightened out), somewhat in the door hinge area....this causes the bottom front of the door not to fit properly, I believe...... I would straighten the metal square tubing that supports the body at that point to conform to the curvature of the body next to the door on the latch side or even a bit more....when this piece is rescrewed back onto the body it should pull the body shape back to match the door curvature........then I would make the screen door frame and attach it to the square tube and the lower bunk structure.....this would hopefully contribute to keeping the trailer shape proper......I`m not sure if this would work to make the door fit better but some folks have rectified the door fit by reducing the arc in that square tube and reinstalling it......I bought a drape type screen door for our 17' Boler but haven`t had to use that screen curtain yet so can`t comment on that but the door on our 13' works and I made the hinge pins a slightly smaller diameter so it`s easy to pull the hinge pins and remove the door it it`s not needed.......the horizontal bars on my door are there to protect the screen when carrying stuff in and out of the trailer.....i.e. not putting elbow thru screen.....
...Benny