List of the proofs that Epic Megagames was really bothered at making Jazz Jackrabbit and wanted to finish as quick as possible and go do better things:

Anims
The bumble bee has a flawless direction changing sprite. It is unused!
Sprites of the bonus mode. Unused too!
Oh, and my favorite: Bubba turning into an angel ... danging unused!
And a lot of other cool, unused stuff ...
No rain particles for Medivo.
No lava particles for Inferno Night.

Game itself:
Layer 5 defining texture mode's speed (absolute and relative).
Unused events, like the lava, the fire, the slide event, yadda yadda ...
Seeing 4 backgrounds when you use 640x480 in Labrat, Hell and Damn (medivo too).
Jazz's sprite and various enemies pass through the walls, and mess up layer 3!
You can easily pass through trees and poles without shooting them.
Layer 8's speed must be 0!
Spikes don't hurt from upside or aside.

Castle
The big pillars on the background have an irregular part.
Layer 8 composable, and various missing stuff in it.
Oh, and that Sonic-like slide thing totally unused and unusable!
When you shoot the armor heads, the shoulders ... The shoulders! That's it!
A lot of unused color indices!

Carrotus:
No slopes on the ceiling.
No corners on the ceiling.
2 unused 2x2 tiles, part of another incomplete project.
The big red carrot is a mixture of sprite colors.
As for the rest ... Carrotus is one of the most usable ones ...

Labrat:
Some mask bugs on the terrain bumps.
Layers 6 and 7 use the same sprites.
You can't understand how layer 5 is supposed to be used.

Colonius:
Backgrounds are copies of the sprite layer.
Mirrored parts in the tileset.
Some unused bricky stuff.
Weird masks on the stairs.

Psychedelic:
Unfitting lower corners.
Pointless bamboo cane. At least I hope it's bamboo ... lol
Wrong masks for the spike event, will always hurt.

Beach of Pirates ... Nah, I'm getting tired of searching for errors, so I'll just write down the ones that I know ...

Inferno:
It's a ... you know what! It is super, super full of bugs!
Layer 6 is designed as a single thing, but loops on the x.
Parts of the soul tree not matching.
Lots of flipped tiles.
Disgusting masks! They make me sick!
No lower part for the spikes tile.
No ceiling edge, and the slope doesn't fit with the rest.
The bone bridges aren't supposed to be warped, even though they are in the levels.
The platform tile doesn't match with the rest of the peninsula, or cursed soil, or whatever ...
The sprite background ... Oh, wait ... I already talked about the masks!
The bridge of atlantean goo doesn't even match with itself!

That's a pity, because Jazz Jackrabbit would have been a great game, with a little more teamwork and less hurry.
I'm sorry, but I'm really disappointed by the shameful behavior that Epic Games had by making it so poor, and most improtantly the ever more shameful behavior they keep on having with all of us everyday. I really wish they had that bit of dignity that every game making group should have. They don't even bother at making the 3rd Jazz Jackrabbit game. This because they're rotten!
But I'm not! I think they should at least make Jazz Jackrabbit 3, and not abuse of their power and say "We're not going to be doing Jazz Jackrabbit", because we're not robots with no feelings.

Epic Games must be shot! Jazz Jackrabbit must be resurrected ... why ... BORN FOR THE FIRST TIME!!!

Jazz Jackrabbit has NEVER EXISTED, since it is not cool the HALF of Sonic the Hedgehog. And this because of those Epic Games TYRANTS!!!