This is already an option with the editor.
Tools...Launch Editor
Create a new file, and save it in the default directory. Go to the Tools grouping, and then the Advancement Cost mechanics tab.
Press the New (Copy) button at the bottom left, and choose "Karma Costs" as the thing to copy.
The search sequence will default to 10 - change that to some lower number. If there's more than one karma cost mechanic, the one with the lowest search sequence will be the one that's used (alphabetical order by name if there's more than one with the same search sequence).
Then, a little further down, find "Quality Cost Multiplier". Change this from 2 to 1.
Now, give your mechanic a new Id - I'd use "MJGKaCost" - MJG being my initials, but you could also use it to identify something about the campaign you'll be using this.
Save the file, close the editor, and then in the Develop menu, choose "Quick reload game system" (enable data file debugging, at the top of the Develop menu, will need to be turned on first).
