The bonuses are the worst, they are exact replicas of already existing levels, except the blocks are 2*2 instead of 1*1. You solve them the same way though. I'm not sure if your bonus level is a copy as well, but it's not a very good level to be honest. The white blocks aren't used at all and all you have to do is two very simple moves. The walls aren't needed and so are the gaps in them. The 50th big level is fine, but it doesn't fit into the series (even if it's supposed to be a special level), but that might just be my opinion.
II - Min
III - Min
IV - Min
V - Min! (First V = Min!)