I've managed to get the lining stitched to the back of the front piece of the etui, and connected the side piece with its inner chamber to the front piece.
I'm glad I did the connecting part with daylight--it made it much easier to see those tiny stitches!
The next stage requires attaching the pocket to the back piece of the etui, then sewing the lining to the back piece, and then (I think) attaching the back piece to the side piece. Then I need to assemble the other side pieces and the drawer that slides into the other side of the etui and the lid, and I have to twist some cords and make some tassels and get all of those bits and pieces attached to this assembly.
The thought of all of this makes me want to lie down with a cold compress on my head.