RE: Wing Spar
I would drill 2 holes into the wing half where the spar has broken.
Insert two pieces of piano wire into those holes.
Glue a piece of wood between the wires
You now have a connecting spar that fits into the spar box...
Have done it on 2 giant scale planes (ten foot wingspan). It really works. And it is a fast and cheap fix.
If you desire, I can send you a picture of it.