This a compilation of the levels from the 2008 Vanilla Level Design Contest (VLDC.) It contains 50 levels which you can play in any order you wish - all of them are open from the start.
Note that even when the game autosaves, it doesn't keep track of which levels have been cleared or which levels you collected the Yoshi coins, so you will have to do that yourself. The level credits file marks how many exits are in each level and which ones contain Yoshi Coins.
I counted 74 unique "exits". At least one was a few alternate paths throughout the level and another door leading to the same boss room. Inconsistent, other levels did this. I could not find a way to get a key in Frozen Cavern Castle either. It seems that if you pick the star run section last, there are munchers instead of spikes above an exit-enabled pipe that leads to the key but there doesn’t seem to be a silver p switch in the room and prior to this, only doors are used.
Actually, maybe it should be 73. I seem to remember a level where both goal taps were set to normal exit.
some levels are still good like Mario ware and the second place level but others are horrible like the ice castle with the puzzle that barely works and the first place level has a bit of a mad palette and the last place one is just a bit awkward I guess but overall good hack.