Just finished it. Great level! I still haven't found the secret ending though... Not even in the level editor
Anyway, this is a great artistic level. I always was fond of floating islands, and this level shows everyone how a floating island should be done.
But, as pretty as this level is, it doesn't play well. First of, I wouldn't classify it as an environmental level. Although easy, Another Strange Dream has some challenges in it (specifically - the umbrella tunnel inside the island's "sewers").
Also, I'm with Talps on the music and desert subjects. This level lacks music; and even if it was designed to be silent, it would have benefited a lot from some background songs. The desert should have at least one more save point. I died in it 4 times and it's horribly frustrating to run back three screens just to die again from a different cactus in the next one.
Still, with these issues aside, Another Strange Dream is a great Knytt Stories level. I would rather not call it a sequel to "A Strange Dream", as it has very little connection to Nifflas' great exploration level, and your level differs a lot from it (both in the art style and the gameplay style).
Seeing as this level (and this entire thread) is just a way to promote you pixel editing program I will criticize it too.
I've played around Pix Army Knife for a while. It's a nice program, and while I wouldn't use it for "regular" Knytt Stories design (creating whole tilesets) its simplicity and easiness of use make it a perfect program to be used alongside with Paint.NET or something like that. One major criticism I find in it are the palettes which come with it. I love the idea of pre-made palettes, each designed for a specific "mood" or "environment", but the low quantity of palettes coming with the program and their low quality are just a turn off.
For the program's next version I suggest adding more palettes and adding more colors to the existing ones.