5 01~5 05 intended
(5 04 Rhythmical is an acceptable variant! You found the exactly same solution to josh.

Have a look at the attached replay of mine

)
5 06 RefleXion: Saving the leftmost glider lemming should be the most challenging thing about this level! I added an obstacle so now it's harder to save that lemming

5 07~5 10 intended
5 11 Lost in an Ice Cave: You are supposed to invest a miner and a basher at the exit area to release the crowd! I didn't notice that one miner is enough to do so..
5 13 System Malfunction: You got the one of the two main tricks!

I think this fix is enough to enforce the another one.
5 14 BlockChain Company Revisited: acceptable

5 15 Simulation FARO: Your solution is cool! But I want you to use both exits

5 16 Facade of Indifference: Almost intended. You only need to find another way to send the slider lemming to the top part

Also the intended solution contain the crowd a bit differently.
5 17 Forgive Us: Wow amazing solution! But I still want you to use every part of the level. So here's the fix!
5 18 One Lemming to Rule Them All: 90%+ intended

You only need to tweak your solution a bit to send the disarmer lemming to the right side of the level.
5 19 Immoral Society: The zombie lemming(who once was a savior of the lemkind

) is supposed to block the lemmings comming to the exit area. Other than that your solution is almost intended.
5 20 Lovebirds Duet: not intended at all

5 12 Butterfly Effect is also a huge backroute, but I can't find any proper way to patch up your backroute. The main trick is quite expensive to pull off in terms of skills so it's not easy to enforce the intended trick.
I think it might be better to take my time before I do something to this level
