I'm suspicious of the uniqueness of the solution to the middle layer of "Ships Pass", but I'm probably missing something. Cool game.
I’m pretty confident about the uniqueness of that one - though the confusion might stem from that puzzle making heavy use of the number of mines remaining as a core clue, and also relies on the player figuring out that…
(Spoiler - Puzzle Logic)
...if a tile is '0'/blank, it can't contain a mine on adjacent timeline layers.In any case, thank you so much for the feedback, and glad you liked the game!