The flesh area has me very confused... I understand there is some kind of puzzle at play here, and the solution is probably very straightforward once you figure it out, but I'm finding it difficult to focus on the puzzle because I'm more busy trying to figure out where the hell I am. I'd suggest either downscaling the flesh area, bringing the "hole" and the doors closer together, or adding some hints.

The Kuro Rena area (Purple area) needs some refinement

For the ‘Slime covers’, there’s a visual glitch that turns the player invisible when there’s more than one.

It happened after the Vac Kuro boss fight, if the player is ‘cubed’ and gets slimed by a normal enemy, the player will turn invisible because there’s more than one ‘cover’. The same happens if the players gets ‘boxed’ from a Mimic Kuro, then normal slime is thrown.

The boss of the area, Kuro Rena has the most problems when trying to get the ‘boss cover’. Seems to prioritize more of the slime throwing overall, and for binding, it targets team members more. The main issue here is when the player gets the ‘boss cover’, there’s a glitch causes the player model to revert back to standard ‘slime cover’ when the boss throws regular slime at the player.

Lastly a thought for team members; Teammates shouldn’t be auto ‘turned’ when corruption reaches max. They should ‘turn’ when HP hits zero. You could change it to only ‘turn’ when HP hits zero, or alternatively, to push the player to prioritize cleaning more, the teammates could take more damage and/or sometimes not listen to commands when completely covered. This way we can have the option to keep both, the player and the teammates 'covered'.

Ah, for the first area with the blue slimes. Could you have the Slime Clone ‘cover’ stay on instead of removing it after the fight? The after effect could be still healing the enemy slimes if left on