How do you expect people to pass this level when you don't give enough keys to drop down, they don't start dropping until you have only 5 moves left, I have popped 4 but that isn't enough...WOW
The keys always drop on the same moves (0s and 5s) and only on those moves. You simply have to ensure that a match occurs under one of the release points on those moves so that there is space for the key to drop.