Driving Raymarine SPX-10 or similar autopilot from VX2



I'm trying to get the above autopilot to be driven by go-to function of 10" VX2. I achieved a small milestone yesterday, but still not working 100%

When port 2 NMEA output was connected to NMEA input on AP at the course computer, no XTE, BTW etc would show on the AP. I moved the connection to the ST6002 controller and the AP now displays above data successfully from the VX2. When track is selected, AP still displays NO DATA and won't lock to waypoint.

I've checked all the sentence outputs and these seem to correlate with the Raymarine requirements (and it does now show XTE, DTW, BTW etc).
I have seen many Raymarine Seatalk processors have problems with NMEA 0183 but work fine if you connect that same NMEA to the back of their control display or purchase their NMEA 0183 to Seatalk converter. I normally recommend you turn on the following NMEA 0183 sentence to drive a pilot. APB, GGA, RMB, RMC, VTG, XTE. If it doesn't work for you, you might talk to Raymarine about suggestions. The Vx2 can put out either v1.5 or v2.0 NMEA 0183 at RS422 signal level (using port 2) or RS232 signal level (using port 4).