With that in mind, here's my first door. It's made of balsa wood, which is mercifully easy to cut. I cut out the basic shape using the template I used for the castle door openings. I scored it with a ruler and pen to imitate boards, and added the Z frame on the back side. I painted it with a thin wash of 2 parts burnt umber and 1 part raw sienna.
I'm making the hinges out of cotton medical tape. Here's picture of the door pinned in place to check fit. I had to pare the door down on all sides (and on the z bracing) to make it fit and move in the door opening.
As I've said before, I find that black polymer clay is really good for imitating wrought iron. I rolled out the clay quite thin and cut out some very simple strap hinges. You could make these quite ornate, if you wanted to. I added small balls of black clay to represent the nails or bolt heads, and baked them.
I then glued the bandage strips onto the door and glued the faux iron hinge on top. The glue I'm using is Alene's Tacky Glue, but any good quality white or wood glue would do.
I made a handle out of the clay, too -- shaping the end and then bending the whole thing over my metal craft knife and flattening the ends, adding small balls of clay for nails again. The resulting handle is good -- a little too bowed, but still quite convincing. I glued the handle to the door.
Then I glued the fabric hinges to the wall and covered them with the clay hinges, and the door is done! (the upper hinge looks VERY crooked in the photo below, but it looks fine in person :)