Good suggestion. I can't enable the PTT in DM780 with listed combination of programs. Like I said previously, I use 2 virtual ports to allow SDR Radio to talk to HRD. When connecting HRD via the virtual serial port to SDR-Radio I use the connect protocol of the Kenwood TS480. This is suggested by the folks at SDR Play. When I try to transmit with DM780 I get an error with the TS480 connection.
I think I'll take a step back and ponder on this some more.