Edit existing power flaw
 

I want to make a teleport spell that needs a standard action to use but for some reason the Increased Action flaw throws up an error when added to a movement effect.
Nothing I've seen in the handbook suggests that this isn't allowed so i would like to edit the flaws data to remove that restriction but i can't find the file for it and i don't want to make a new flaw that is otherwise identical

Use Add Copy on the Flaw, noting the id. Give it a new id, modify it, and put the old id in the Replaces field.

It's the standard way to do it, for better or for worse.