Wow, this game is great! It looks good, I love the frogger parts, just an all around awesome package. I do agree that the button spamming is kind of annoying but that could be easily fixed (just let the player hold down the button to mine).
I think the timer works great, I love how it forces you to think about which route might be the most profitable without taking too long to mine.
My score was 337 on the first try, but I'll definitely come back to improve it!