I have been runnung a D100(Ver5.4.3) and AP74 and a Garmin 295 for the last while and still cannot get the autopilot to work in nav mode, however hdg, trk appear to function correctly. The CDI feature is also not active. The D100 appears to communicate with the GPS (see attached photo), as the magenta data is presented in the HSI window. I have configured the serial setting bewtween 4800/9600/auto , does not make any difference to the nav requirement. Any suggestions?