I just installed the AVIC-8200NEX. At least on this unit, the yellow and red wires should be connected as color-coded and not switched as per the directions on
Porsche Boxster Avic D3 Installation Instructions - DIY Articles - Boxster (986) - Accessories - RennTech.org Community
From the Pioneer manual, yellow is "To terminal supplied with power regardless of ignition switch position," and red is "To electric terminal controlled by ignition switch (12 V DC) ON/OFF." If you follow the great instructions above, you'll lose your presets when you remove the key.
Thanks to the community for the thorough and detailed write-ups and pics. Now, I just need to pull the drivers seat so I can connect the reverse wire :-).