Yet another fix for Crossed. I'm really not sure why it occasionally outputs completely blank puzzles.
All very odd.

I think it's a memory/variable issue, as it seems to be happening most often when the puzzle takes too long to generate, and curiously empties itself as it does so!

Anyway, I've rewritten chunks of it, yet again, in the hopes that it'll finally fix the issue, but ... yet again, it's reset the "Yesterday's Solution" content, so apologies for that.