Thanks Tyler. Yep, couldn't get it to do anything below half throttle, that's why I started mucking around with the High/Low needles, thought the Low circuit was blocked. Just been tweaking it and it's running well enough on half to full throttle with H turned out two turns, don't really need it to be idling.
It's a toy though. I borrow either a Stihl BR800 or 600 backpack now and then to do our walking paths, this little thing will be handy around the verandahs and carport.