Roll jumps are much easier than scan dashes, you should forget the kip dash for the moment.
Quote from medigodoom:
And how would having that white door previously scanned make it easier? I can't even move when I scan it.
If you're good with Metroid Prime 1 sequence breaking, load it up and practice dash jumping. Moving after you scan the door should be more or less the same as dash jumping on a scan point that's already been scanned. I remember when I started sequence breaking Metroid, I had trouble with dash jumps. It took me a few days to get Space Jump First right, and even then I still hadn't mastered dash jumps. Now I can get it on my first try every time. It just goes to show that practice makes perfect. You need to do all in this order but as quick as you can: start moving, hit L, press B. Move stick down left, release L, quickly press L again but not all the way and hold it, 1.5 seconds later jump. That's what you should do for the scan dash method.