Alright so I played some more:
"The Spikes have Eyes" by Skullwalker, I said in my previous post I suck at any flying Power-Up. And what do you know? I gave up fairly quickly I'm afraid.
Then Mike321's "First Level". I thought I knew what to do, but I'm not sure now. I figured I needed to use the first Lakitu to get on the ?-block halfway and use it to get over the Goomba/Koopa/Piranha stacks, but I couldn't make it in time. I suspect their's some clever trick, but I wasn't smart enough...
Which also goes for Cone's "Level 2". It doesn't look difficult, but, I'm not seeing it :-| .
So then I got annoyed because I couldn't your levels, and I went to something that looked self exlanatory, like "Make it rain-but run to stay dry" by Curmudgeon. Which is easy because you just run, so I tried "Airship Armada". This one looks great! The esthetics of the small ships are excellent. It's a good challenge, and I hate the jumping on the Koopas, but I stuck to it .
Finally, I played MDMAlliance's "Easy fun" and while is was that, I still managed to noob out on one of the boos .
This is great you guys, I'll go back to creating now .