Update as promised and it’s good news! The extra 4GB RAM arrived on Monday and I have installed it (now up to 8GB) and run the various restarts as instructed by my laptop. I’ve jumped on to various routes on Makuri Island and everything appears to be working correctly, all of my power, cadence, heart rate information is being displayed along with the nearby zwifters list. So far so good, although I see that another upgrade has just landed tonight (fingers crossed). Looks like it might have been as simple as my laptop not having enough RAM to run the additional graphics on Makuri Island. Now that I’ve ridden it a few times there does seem to be a lot going on, I’m sure they will be healthy distractions for the tougher sessions!
Thanks to everyone for your help, advice and patience on this, it is very much appreciated.