After filling and sanding, the door was ready for a few coats of paint (turning a dark brown door into a yellow one, it turns out, takes a bit more than a few coats...), and then for its new hardware:
Once the knob and dead bolts were in place, I drilled out holes in the jamb for them, and installed the strike:
I then painted said jamb and strike...
...And the door is now fully functional:
I painted the mill work with the maroon I've chosen for the exterior trim, and replaced the glass in the window with a piece of bead board, painted to match the door:
The rest of the cart, once the siding is on, will be painted in this same yellow. Because it's a little on the mustardy side, I'll probably get a can of slightly paler yellow and paint on a subtle ghosted bamboo pattern or some such to break it up a bit. But for now, I'm liking the color.
I also started work on gluing the board insulation to the ceiling/roof panels, and getting them into place. The middle section is the first one I've completed. It sits nice and flush with the joists: