So, I went my third playthrough of this level set (two first were in spring-summer 2012, v3 and v7 of LPDOS), and I recorded my solutions now for all 150 levels in v7. Again, I tried to make natural solutions, but in some cases I tried to save as many as possible.
Challenge/alternative solutions will come later.
Some notes:
Medi 18: Going Under - 100% saved
Medi 27: Take A Dive - 98% saved
Danger 16: Grounded! - 85% saved,
one guy achieved this a lot earlier than me, though.
Danger 21: It's the Latest Craze! - 95% saved
Danger 23: Lair of the Fallen Lemming - 98% saved, okay my original solution used the bomber there where I used the miner in this solution.
Danger 30: The Hideout - 98% saved
PSYCHO 5: Lightspeed Lemming - 91% saved, this was one of the three Fire levels I had troubles with back then (Danger 22 and PSYCHO 2 being the other ones), this is pretty hard and I remember that when I solved this, I saved an extra lemming by accident with this solution.
PSYCHO 6: The Bulldozer - Now I remember that my original solution used this 'blocker cancelling trigger areas'-glitch.
PSYCHO 13: Go High, Go Low - Steel digging glitch used and saved extra lemmings. I should look for a glitchless solution, too.
PSYCHO 17: Meeting Spot - My original solution used 'climber stuck in the ceiling'-glitch, here's a glitchless solution saving 90%.
PSYCHO 19: The Perfect Nightmare - My original solution used steel digging glitch, here's a glitchless solution.
PSYCHO 24: Gone In A Flash - Steel digging glitch used. I should look for a glitchless solution, too.
PSYCHO 29: No Salvation V - My original solution used 'blocker cancelling trigger areas'-glitch, here's a glitchless solution.
PSYCHO 30: Hellfire! - My solution saves one climber.
I haven't watched the intended solutions, so it'll be easier for me to find other solutions still.