Yes, there are some puzzles. Though I think it would be good to have a hint system with individual drawings (so that each puzzle would become approachable for most people). For a good number of them I have difficulty in identifying how (or where) to start.
Still very good though (if I had to solve one I would try to find an easy one and try to solve that). A hint system would complement it even more.
Yikes. I get the distinct impression that the solutions are not in geometry but in algebraic trigonometry (or trigonometric algebra).
IOW, rather than answers like angle c = root (b+a)2 or somesuch that can be illustrated, it'll be angle c = cos(sin(a)/(cotan(b))) or someothersuch that can't be illustrated.