Love it, also love the main menu making use of the putt mechanic, the main menu almost acts as a tutorial which is awesome and makes sure the player knows how to play before they start.
I did manage to get the lose screen to appear as well as the win screen the first time (I was cutting it real close getting to the end that time). The win screen was still in front though so it wasn't a problem, just a visual quirk
Really nice work, and a working leaderboard too!