This is pretty good work design wise. There are a few problems though.
Left/Right warps should be on the bottom, not the middle like you have:
The death effect for the penguin is missing, and there's a snow graphic where the SMW goal should be:
The player can get stuck or glitch in these three areas:
Fix these and you have a very well made level on your hands.
*sip* Don't talk to me until I've had my morning coffee.