Looking good m8, you've managed to turn most of the stumbling blocks into stepping stones, hope we get to see her sailing soon.
Good info on the camber, I was wondering why I wasn't going faster in my sailing sculler, that's probably the reason, new mast and sail are on the drawing board though :)
most junk rigs have boltropes in leech and luff to reinforce them, Your sail is a lot higher peaked than mine, so I'm not sure my experience really applies.
on your sail it looks like you need to use the yard hauling parel to set your sail, on mine all it does is hold the sail close to the mast so there's no need to do more than snug it up, once I start reefing I don't usually bother with the YHP at all. while on your sail you need to cinch the YHP tight to get your sail to set at all, you might find moving your halyard attachment point around helps set the sail better so you don't have to pull your yard hauling parrel so tight.
also, the sail sets a lot differently when full of wind, it'd be nice if you could play around with the plastic sail on the water for a bit so you could see first hand how all the bits and bobs on a junk rig work together before you make your sail.
Your battens look a bit big for the size of the sail, I'm just guessing but it looks like about 75 sq ft, about the same as mine which has 7/8" X 5/8" X 8'(21mm X 15mm X 2.4m) battens.
Have you considered using something like an upper luff hauling parel to pull the top of your sail back when shunting? It'd give you a lot more balance and you wouldn't need such a high yard angle to clear the mast, your sail would probably set better as well, as is you're likely need a pretty big rudder if you want to sail downwind.
Bill
PS: wetsuits are cheap and will keep you roasty and toasty when sailing in the winter, I wear mine under jogging pants and a jacket.