Hi there.
I think I've found a bug with UIButtons and UIButtonKeys. Our UI is going to be controlled entirely with a controller. I made a simple 3D UI test with three buttons connected with UIButtonKeys. If you press and HOLD the accept button (JoystickButton0) and then use the vertical axis, the next button is highlighted but the active button is still the first one. I found that UICamera.ProcessOthers sends the notification regardless of what buttons are pressed. I think the correct behaviour would be to not allow moving if a button is being pressed.
We have NGUI pro, if a bugfix is released in the repository, would you mind to contact me to download it?
Thank you!