It also occasionally generates one where it can’t determine whether the game is solvable or not, which is probably due to search space limitations. I’ve won a couple of those, but they’re risky to start in the first place!

I kinda like those. I've also won couple of them and one of them was quite close to a win and it was always unwinnable at the very last parts (I tried the same seed 3-4 times).

Yeah, I get the logic and with the current system it might cause a long start if it runs into a bad string since it should also skip undeterminable games. Maybe someone should rewrite it in Rust. /j