@AWOL
Yes it appears to work - having made the claim I thought I'd better check - I have uploaded it to an UNO, error fixed, The LEDs on the outputs cycle and the LCD reads. However, see title, not soak tested and not yet connected to the RX module.
If the moderators didn't realise I am a newbie, then I can only assume it must be common practice to take the mickey out of programmers who post errors in their code - bloody confused me.... no mind, as long as I know for the future.