Yeah, I know it's minesweeper, with a fun take on it. And the thing is- I love puzzle games, I think, I'm good at them for most of the time, but for some reason minesweeper just defeats me :D Especially with ghosts chasing me :D
As for the leaderboards- I use lootlocker. They have a free licence for jam games, are easy to implement in game, and always worked for me.