3/5: Would have rated higher but I got stuck in the second room of the Desert Temple. The room with the key and P switch. I could not jump down to the P Switch at all as Mario's jump height kept bringing me to the floor above the pit I needed the cross. I know you said it requires knowledge of Super Mario World mechanics but it looks like a jump using the key is needed while falling into the pit to get across to the P switch. In my opinion that isn't "normal mechanics." That's pulling off a kiazo level trick and one I can not pull off. The graphics were great and the music made for an unsettling theme. I wish I could have made it further.
This was a pretty fun hack to play through and I wouldn't fully go as far as it say it's a hard hack but the length of the single level does leave you a little exhausted by the end if you play it straight through.