The demo review.
You played my level so I played yours so heres the review, I know it's not finished but some levels were, so here is what I think.
Difficulty/Challenge: 6.0: There is some hard aspects of this but it only comes from the virtually impossible platforming, or the get 700 ring special stages, otherwise it's not very hard.
Level Design: 5.5: Too many times did I find myself running around in what seemed like a giant box, in some levels namely the second one, I found myself running around in an oversized maze, just to find out that the factory had the exit sign, some acts were way too uninspired, crisis ship act 2 feels like a much speed zone from next gen, but in reality it takes too long to go though.
Problems/Glitches: 4.0: The more problems the lower the score, some missing textures, twitchy walls, and wierd texture pop up, as well as the retina numbing nextures found in casino carnival, the levels are overspacy, missing bosses, and the giant box feeling.
Oringinality/Cool Stuff: 4.5: Some intresting textures causing some feeling in the box like level disign, some intresting platforming, the stairs were cool, like the hud, some intresting level designing in spots, the bouncing on enemies in the mine zones boss was fun.
Individual levels: 5.0 (4.9)
Emerald hill zone 1: 5.5: Cool water, underwater doors.
Emerald hill zone 2: 3.5: Box-like maze.
Emerald hill zone 3: 2.5: No boss, decent arena.
Metal maze zone 1: 5.0: Better looking box-like maze.
Metal maze zone 2: 3.0: Short, slime, stuff.
Metal maze zone 3: 3.5: Bouncy, still no boss.
Leaf forest zone 1: 6.0: Stairs, wood, jungle, pit.
Leaf forest zone 2: 6.5: Longer, wood, jungle, pit, no stairs.
Leaf forest zone 3: 3.0: I forgot about it, still no boss.
Casino carnival zone 1: 6.0: Seizures
Casino carnival zone 2: 6.0: Recoved a bit, but whats with these springs.
Casino carnical zone 3: 7.5: A boss.
Crisis ship zone 1: 4.0: Missing textures.
Crisis ship zone 2: 4.5: Missing effort.
Crisis ship zone 3: 7.5: Missing...Wait missing nothing.
Darkness city zone 1: 5.0: City, Giant ring, Balance beam ave.
Nothing else I wanna rate.
Overall: 5.0: Too unispired, the whole thing feels like one emotionless blob, wheres the thrill, that's what sonic games are all about, nothing against you, but your strive too make 20 levels, has left you with 5 levels, in need of love and attention, I played a lot of level packs, and this one just seems to be missing something, something that most level packs have.
So that's the review, I don't hate what you have so far, it just feels too imcomplete, even in those completed levels. I hope it serves at constructive critisism, please don't hate me after this, just wanted to tell you what I thought, not to flame you or your level pack.