Yup. The Amiga version is the original, so the DOS version relaxed the requirements on several levels. Let's see if I can remember all of them:
Fun 15 -- 80% on Amiga/Mac, 50% on DOS. Not that it matters as the normal "block the crowd" method saves 97% in any case.
Taxing 22 -- 100% on Amiga/Mac, 80% on DOS. When I played this as a kid, I solved it with a very elegant short-route solution, but there are several possible methods including the long route.
Taxing 25 -- Already mentioned.
Mayhem 4 -- 100%, 10 bashers only on Amiga/Mac, 80%, 20 bashers, 10 bombers on DOS.
Mayhem 15 -- 95%, 2 minutes on Amiga/Mac, 75%, 3 minutes on DOS. This makes the DOS level easier than its Tricky equivalent
Mayhem 26 -- 90%, 10 bombers, blockers, builders on Amiga/Mac, 75%, 20 bombers, blockers, buiders on DOS. Note that the Amiga version has 100 lemmings, so you can lose 10. On the Mac, they forgot to adjust the percentage, so you can only lose
eight, making this level ridiculously difficult.