Having referred to various articles I finally have my PC communicating with my FTDX3000 and HRD seems to work fine over USB Cat link.
However, struggling with wsjt-x (1.7) - in the radio config, I'm selecting the HRD config which I know works and I can now change bands etc and the waterfall is displaying the strong signals on 20M.
I've installed an alternative time reference but . . .no decode of spots.
Any suggestions gratefully received