Cool idea, here's my take on it so far:
Pros: Neat Graphical Style, good Mechanics, not very buggy at all.
Cons: The 'Next level' moving is painfully slow, and the load/unloading of dirt should move a little faster.
Musically, mixed feelings. Like the general style of what you were doing, but the 'digu digu' should maybe on some actual instrument. Other than that, very nice prototype!