The Flashlight toggle has to be cooked into the SystemUI.apk. The only thing I can recommend is taking the SystemUI.apk from a ROM that has it, like S&T or you could flash OZOP Control. The link is in my signature.
You should make a nandroid just in case.
It should be compatible but haven't had a chance to test and didn't receive feedback when I asked for compatibility in this thread.
If you try OZOP Control feedback would be very helpful with releasing my Mod section for other rom.