Cool game! I have same idea some times ago, but too lazy to implement, and be very surprised!
But progression mode some times buggy... After ~4th layer every next levels w/o mines and game freezes with black screen at end.
My wife and me played only web-latest chrome version already.
We get two full freezes as I describer above and many just an empty levels in middle of game, and an empty levels don't reveal top layers at all. (May be, break top revealing to next levels, but i am not sure) Me be it's give You some clues...