I was going to ask this very same question. The title of your post though doesn't say 'windowed' so I didn't know what your topic was until I opened it.

Anyway, question still stands. Might we play this in windowed?

Yep, with left alt+enter. I don't know why but the right alt isn't toggling window mode.

That' bishop's puzzle is one of the hardest puzzles I've ever done in a video game! Not that I do lots of puzzle games, but geeeebus, it's hard.

I have my "Let's Play" of this game, and I solve the puzzle serendipitous.

However I know the rule.

You can't move the bishops in line of the killing line of site, from an enemy bishop.
Th rule is really that simple, nothing complex about it.

Sure knowing the order of movement might be hard, based on that rule, but the rule itself is simple.

^_^

Yep, the rule is easy.