vim and notepad support SoF. 
Seriously though, I don't normally mess with GUI editors so I'm not too helpful. Editing by hand is usually a sure way to do it. You can compile the utils\spell_explorer to see raw info about your edits. 
 
But it's more complicated and not as friendly. 
		
	
		
		
		
		
		
		
			
		
		
		
		
		
		
	
		
		
	
	
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