Right, an update...that I don't fully understand. Having tested sending PC from my PC and seeing it working correctly, I went with hit and miss stuff on my HX.
In short, it's all working amazingly, by simply changing the Midi Channel to "2", so on the HX it looks like this:
Command: BankPC
Midi CH: 2
CC00: Off
CC32: Off
Prog: as per table, e.g. 0 = Bank 1, Rig 1, and 5 = Bank 2, Rig 2 and so on
Attached a lookup table to help anyone if it helps, and if someone can improve my understanding to tell me why this works and other channels don't, please do!