Thank you everyone for your replies so far, your input is very much appreciated.
Currently I'm using the "Standard RGBW" driver, not the Advanced version which didn't seem able to even turn the lamp on.
Scouring old posts I find this has been an issue for people before:
I don't want to be a nuisance here but if we can solve this I would love to leave breadcrumbs for others to follow to help them. So, I have new threads to follow thanks to your postings, I've contacted the supplier (Ajax) today to ask them as they do list Hubitat as a compatible hub and I want to invest some time getting familiar with the logs.
I'm away from home until Tuesday night so I will post an update then, either with the answer or more information.
Thanks again for your patience with "the newbie" 
