You can think of the levels as levels that didn't make it into the original 120.
If these were in the original game, what spot of Fun, Tricky Taxing, and Mayhem will they be? of course those early tutorial levels will be in the Fun section. "with a little from my Lem" and "No justice for the hero" would be Mayhem, since those were one of the levels that took me a long time to figure out. Note that this was during the time when I got back into playing Lemmings again and didn't know any tricks and how a lot of stuff work. I only messed around a lot in the levels in the SNES Lemmings and played 2 player mode, so I never learned how to beat the game, until Lemmings PSP.
I played the Lemmini levels and found out something wrong with "Notch what you think it is!" There's a 100% solution that seems to be more difficult to pull off in Lemmini, then it is on PSP and Lemmix. It's in the part where you use the builder. In Lemmini, you only have one pixel of a chance to turn the Lemming into a builder to cover the gap, before the Lemming behind him falls and dies. Maybe the length of the stairs in Lemmini is shorter? This is not the first time I have seen a level from Lemmix played differently in Lemmini. It happened with my old pillar level.
Yeah that exit trigger area needs to be fixed. It's in the wrong spot.