or i magically hold some one and strangle them with a cord. My magic held them still when they would have otherwise ran away or fought back. My magic changed reality but the cord did the killing. This is why the laws of magic suck there good for the story lousy for game play.
They are good for the story and the gameplay because in fate, they're pretty much the same thing. As the GM you set the meta-rules. If you say that counts as law-breaking, then it counts. Just talk it out with your players. If they agree cool. If they don't, then maybe you negotiate, or maybe you don't.
That's the whole point of my comment. OP asked how to have mortal magic, self-transformation play into law-breaking. Tighten up your rules for what constitutes law-breaking. Transform yourself, okay. Transform another, not okay. Transform and do damage, okay. Transform and kill, not okay. Transform aspects, never okay. Etc., etc., etc.
Personally, I'd count your example as law-breaking.