Well as I was trying to figure out the ladder glitches in the genesis version, I found a time save in Bell Castle Act 3. This occurs at the ladder at frame 08693. I found out you can cancel your ladder slide by pressing up. Since we climbed down quite a ways I figured sliding down a bit and then canceling it would be faster. It ended up being about 20 frames faster.
But, of course... The swinging bells later on strike again. This time I had to drill to bypass 3 of them. It still came out like 5 frames ahead at that point though so I kept going. lost another frame saved somewhere, I think one of the upcoming ladders. Overall savings was 4 frames, but I'm confident something better can be done if you wanted to take a quick look.
Here's the file:
http://tasvideos.org/userfiles/info/47810233977187429
Edit: Just downloaded your script r57shell. It seems interesting so I'm gonna take a look in a bit.
Edit2: Found another improvement, at frame 30367 in my improved file above, press jump. This lands on the very edge of the first star platform which you can then jump off of, and barely make it onto the third one (skipping the second one entirely). You have to drill at the very last second before hitting the spikes (around frame 30466). I don't have enough time to update the entire level, but just wanted to post this improvement before I go to bed.
edit3(sorry): at first glance, a frame can be saved by pressing C at frame 30172, to trigger the trampoline rather than pressing D+L+B the frame before that. It should trigger it 1 frame faster.