Prevoiusly I said i have bugs - airplane mdoe bug, and some others i didn;t decribe.
But i came drom 2X,through 3x and 3.1X to 4X and 4,5X versions. Fully wipe is recomended when going to 4.5X. In other way bugs have open way to yours P500
And yes -GTR theme cuases bugs 0 I don;t know why, but switching to system repairs all.