In area 2, bottom center 10x12 puzzle is unsolvable by logic only--there are multiple solutions, some of which the game considers incorrect. I checked with a picross solver to make sure. (see image) 
Solver: teal nonogram solver
2 years ago(+3)
I believe the 15x15 has the same issue, this is as far as I could get logically. Ran it through the solver and it got just as far.
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The issue appears when I try to force it further:
The resulting puzzle cannot be solved!
I believe the 15x15 can be solved by guesswork, but unfortunately not by pure logic.