When using transitions on certain nested sequences my final renders get a color shift during the transition using PP CS 5.5. If I use PP CS 4.0 they render just fine. Someone else had mentioned this as well. I don't know if the Mercury Playback Engine should be tweaked or just scrapped. It is nice to edit several layers of native AVCHD with filters in real-time using PP CS 5.5 but the quality needs to top priority as opposed to performance.