Same issue here..
changing the GetComponentInparent<>() to .transform.parent.GetComponent<>()
Slows the whole Editor down as hell..
The question is, why is NGUI generating all those Errors about GetComponentInParent?
And why aren´t there more People with that problem?
I updated like before ..
Deleting NGUI Folder,
Import updated NGUI..
EDIT - IMPORTANT
For all that haven´t allready recognized it.. The new NGUI version needs a Unity Update to 4.5.2
But this info is only visible, if you take a look at the Asset Store NGUI page.. if you just update via your Asset Table, you won´t get it..
And i need to say - That´s so fucking bad! I´m not a fan of updating the whole engine, while i´m in the middle of creating a game.. That´s the main reason of fatal errors, that can destroy the complete work..
So.. PLEASE.. no more update forcing, just for NGUI updates ._.