Cotton 100%

This achievement (along with the Beginner, Intermediate and Advanced achievements) is awarded for reaching the score in Standard mode without dying. When I say dying I mean using a continue which sets you score to zero. Since you can rewind the game with in this mode by default you shouldn't have any issue with dying. The rest of the score achievements are pretty much guaranteed if you finish the game. However this one is just a bit out of the realm of possibility by playing normally. Depending on your Tea Time performance you can realistically expect more than 475.000 points. For comparison I got 499.000 for my first try but I don't think I could have improved it much.

The only surefire way to achieve 500.000 is to AVOID picking up anything during Tea Time. This shouldn't be a problem by abusing the rewind function. Every time you can succesfully avoid all the TT bonuses you will get 37.000 points as a bonus. If you can avoid TT two or three times you should get 500k with ease near the end of the game. Maybe even much earlier if you avoid every TT.