Aesthetically, the level needs serious improvements The first and the last sections seem alienated from the volcanic theme, and the thwomps seem out of place. There are loads of cutoffs especially in the first and second sections:
The gameplay suffers from serious issues as well. Jumping in the water at the beginning (the water under the moving platforms) will get the player killed because there's no way out. I do like the use of moving layers, however. There's an area where you have to wait for the moving ground to get close and I think you should add SMW lines to make the moving ground more obvious. I was inclined to make a blind jump because I couldn't see the moving ground.The second section made me realize how little this level revolves around the volcano theme. The volcano looks incredibly barren as there are no scenery objects. You should have added a ceiling in the volcano section and walls on all sides to make it look more appealing. The way you hid the keyhole was ingenious, but also pretty hard to figure out.
Other than that, the level is of average quality and needs improvements but it's generally OK. Good work!