runouw.com

The sign in the first room is difficult to read, and of course you won't know not to read it until after you have read it.
In the area, you also have a Sling Star that has no value currently and a small gap between the sand slope and the edge of the cage:
it's just enough for you to wander into and slowly get crushed to death inescapably in.

After I used the pipe, I tried to go back in (maybe there would be a 1-up) and instead I got crushed, losing 1/4 of my HP.
You should replace this pipe with a no-warp pipe if you are meant to not warp through it.

There are also holes in your background tiling, done intentionally I think. You should honestly fill it in my opinion.
You should also use different tiles for the slopes, as they do not look appealing to me.

If you hit the switch and fall down, you cannot get back up until the switch runs out: it blocks the way.
You don't need the switch blocks anyway: you can reach the star by triple jumping and all the blocks do is make unsightly holes in the background.

The next room: most of the obstacles can be avoided, the Sling Star and water bottle are not needed, and there's water cutoff.
My computer is also beginning to lag starting here...

The third room: There is a door you cannot see, which you must go through to progress. It is blocked from view by the metal cage.

Fourth room: If you decide to go DOWN first, and into the tunnel with the breakable blocks, you cannot get out. You'd have to reset.
I went up first and got the Hover Fludd, but it's tough to get out unharmed even if you do that. Also: lava cutoff.
Cutoff is a very easy graphical issue to fix... you need to take the time to double-check where you're putting your lava/water and border it with something. Anything!

I didn't see the door the first time for some reason... that's probably my fault.

In the next room, I went down to read the sign and ended up teleported to the next room: I didn't get the red coin in that room yet...
You should put a door or pipe to let the player go back to the last level so that these things don't happen.

In the next two rooms, background cutoff.

In that second room, water cutoff as well, and you should really only have a few coins if you want a challenge.

The pipe to take you back kills you. You must go in this pipe to win; thus, the level is impossible.

This level, all things considered, has a lot of minor flaws and one very big one: the level cannot be completed. So, it gets two stars from me.

Fix the pipe at the end and this will get three stars.

@HickRanger I know that it's hard to read that sign in the first room, my idea was that they would probably just give up trying to read it until the end. Also about that sling star that is there for no apparent reason, I decided to keep it in the level because I wanted people to be able to see what the first level would have looked like if there wasn't any cage there to prevent them from seeing it.
About that space between the cage and the slope I know that this happens and I decided to keep it in because it was just too hilarious to take out. ( also if you manage to come up with the idea to use a hover fludd while diving into that small space, sometimes you go through the cage and right beside it. If you succeed in doing this without a fludd though you will be forever stuck there.
I decided to make the pipe hurt you and not have a non warping pipe because I thought it would get the message through clearer than a non warping pipe.(though I made sure that if they did do that that they could get their health back with a blue coin.
I know that there are holes in the tilling, and usually it is for switch controlled blocks. And if you are skilled enough to get the invisibility cap without using the switch blocks then good for you.
About the room where you apparently can't see the door to progress, I thought that my arrow would point you in the direction that you needed to go to get to the door eventually.
About the fourth room, I know that you won't be able to complete it if you go down first, I just thought that most people (Maybe not you) would go for the fludd first considering that it would probably help the player.
About the room where you didn't get the red coin, if you go down where you read the sign and end up in that small area with the door, (you may not have noticed because it is hard to but. . .) there is a warp pipe directly under that door to go back.
About the room with the water cutoff, I know that there is an abundance of coins in this area, but for some people it might take a bit to figure out what to do with everything in there.
About the room with the 'Killing pipe', I know that if you don't enter that pipe properly it will damage you (because of the flipping platforms), but if you enter it fast enough it will warp you to where you need to go to finish the level (Trust me, this part of the level I tested many times).

Thanks again for the feedback!

~Nuclear_Blaze