I finally was able to power up the entire panel last evening and pulled the RV-10 out of the hanger to test both the GTN650 and the AFS GPS. I have a pair of 4500s and a 3400sMFD. I also have Gemini PFD installed. I configured all the EFIS and GTN650 ports appropriately.

EFIS #1
GNAV1=Remote ARINC
GNAV2=Serial Port #4
Serial Port#4= AFS GPS
Serial Port#1=ATVN/ARNAV (GTN650 Serial)

EFIS#2
GNAV1=Serial Port #4
GNAV2=Remote GPS
Serial Port#4= ARINC
Serial Port#1=ATVN/ARNAV (GTN650 Serial)

EFIS#3
GNAV1=Remote ARINC
GNAV2=Remote GPS

Gemini PFD has the same serial feed from the GTN650 as Serial Port#1 on EFIS#1 and EFIS#2.

Question#1: Should the GTN650 serial inputs be defined at GNAV device? I'm assuming they should be defined, but I haven't configured that as of yet.

Question#2: The GTN650 is showing a track of 271. SRC on EFIS#1-#3 is set to GNAV1. Heading on EFIS#1 is 285, EFIS#2 is 276, EFIS#3 is 276, and the Gemini is 276. Since the aircraft is stationary, I would assume that heading and track should be identical. I don't understand why all displays aren't showing a heading of 271. Additionally, why are the all showing 276, with the exception of EFIS #1. I'm assuming that either I'm not understanding something correctly, or perhaps I haven't configured something properly.

Question#3: I seem to recall from a previous post that the AFS GPS came pre-configured. Is my recollection correct? I'm getting a GPS Integrety error. Is the best way to troubleshoot to hook up to a PC and validate the settings?