When you set up in the KK the axis are linked so if you adjust one it copies over to the other , you should not have an I gain of zero , ok lets say we are adjusting the roll axis
we set the I to zero for now then up the P gain till the quad has a fast wobble ,now we lower it about 5 points at a time till the wobble has gone then do some fast roll and stops as long as the wobble is not there when you stop the quad thats spot on ,now bring up the I gain till you get a slow wobble again bring it down 5 points at a time till it stops the wobble now do the same test fast sudden roll and stop
if there is no wobble on the stop then thats it all done , Jackson found a great video of P and I gains I will see if i can find it , this is it its not a quad but still works the same