Sorry, I am tired and you are right. I did figure out the problem. I had a "FadeDone" callback that apparently gets called both ways (forward and backward) when done in NGUI 3.x. In that FadeDone callback I was telling it to bounce the other way (for a old text fade out then a new text fade in effect). Because of the change in NGUI 3.x it was just bouncing back and force and quickly causing a stack overflow.