I've found some more video footage of Murali with the bloke himself explaining what he does and the more I look into it the more it become unfathomable and totally unique to him, but......
It seems with regards the offspin and the legspin that he doesn't do anything with his fingers at all and that it's more to do with his shoulder and the rotation of his arm. But the main difference to virtually everyone else is the fact that he rotates his arm and wrist in the opposite direction. If you try this - it is possible but feels very unnatural. I've been doing it today and video-ing it and there's a fair likeness between what I'm doing and what he does. I'm now thinking if I could master this rotation of the arm could I possibly discover the nuances of the delivery to make it turn both ways? Or even better click the ball out of my fingers using the flipper technique?
I think I maybe going to a sports hall tonight with Joe and if we do we'll take the camera and might have a go at this and see if I can bowl with the rotated wrist and arm in the Murali manner and see what happens?