Ok, videos attached, hopefully this will work.
They each have a few re-records which are from save-stating at the beginning of the level, to stop having to reload each time.
Most of the runs exploit the scoring method where Sonic stays in a combo as long as he does not leave and touch the ground after hitting an enemy.
Only Labyrinth 1 and Labyrinth 3 are current records, so don't watch the others if you don't care lol.
The Scrap Brain 2 one is a bit weird because you have to enter the 3rd pipe with exactly 49 rings, and since there is no time pressure I left out lots of different ones at the beginning of the level. :)