Well done Hugh, I was pretty confident that it was a guiding issue as I have seen it too many times with my own setup. Another thing it could have been is slippage on your axes. Just make sure all the knobs are tight before you start guiding.
Andrew
Thanks guys, very relieved!
Got a couple of hours of the Rosette and the setup looks like it's working pretty well. This is without a flattener too and it looks good.