As far as I can remember.
Fun 20(We Are Now At Lemcon One) - Changed to "Sega One"
Fun 22(A Beast Of A Level) - Changed to "Go For It"
Fun 26(Nightmare On Lem Street) - Changed to "Sega Two"
Tricky 14(Menace) - Same name but new level
Tricky 25(Cascade) - Changed to "Sega Three"
Taxing 15(What An Awesome Level) - Same name but new level
Taxing 21(Feel The Heat) - Changed to "Sega Four"
Taxing 30(We All Fall Down) - Changed to "Sega Five"
Mayhem 9(Curse Of The Pharaohs) - Changed to "Sega One" (Harder version)
Mayhem 12(The Far Side) - Changed to "Sega Two" (Harder version)
Mayhem 13(The Great Lemming Caper) - Changed to "Sega Three" (Harder version)
Mayhem 16(Just A Minute) - Although still called "Just A Minute", has two minutes
Mayhem 17(Stepping Stones) - Same name but new level (Harder version of Tricky 12)
Mayhem 18(And Then There Were Four) - Changed to "Sega Four" (Harder version)
Mayhem 21(With A Twist Of Lemming Please) - Same name but new level (Identical to PC version Taxing 21)
Mayhem 22(A BeastII Of A Level) - Changed to "Nearly There"
Mayhem 27(Just A Minute Part 2) - Although still called "Just A Minute Part 2", has two minutes
Mayhem 29(Save Me) - Changed to "Sega Five" (Harder version)
There's probably a few more that I can't remember though.
