bugxorz r ur worst enemy
...What?
EDIT: I guess I should post something actually constructive.
I would advise that you should use non-default tilesets, and I would
very strongly advise you use objects, at least. Unless you mean custom objects. Then that's optional.
EDIT2: I downloaded this, and it's very bad. Sorry, but a lot of it is pretty boring, no pretty graphics. Also, just using a lot of enemies doesn't make it fun. Have challenges. Also, there's a wallswim in the 6th and 7th screen. Oh and, before I forcet, have grass on Layer 2, not 3.
EDIT3: Wow...The 10th screen is pure fail. The white trap is on a 3rd layer tile, so it glitches up, and it's visually bad. Please play through your level yourself before you send it out to the public.