you need :
1. flash decompiler
2. adobe flash cs3 or latest version
you must :
1. download original files swf from ninjasaga
2. decompiler it.
3. open fla files and adobe cs
4. open folder autoscript cs3.
5. change the code with any code you want. (you must have knowledge about flash development)
6. publish the fla,
7. you got new swf with your script.
8. try it on your fiddler.
9. trial n error is usually.