Thanks for updating the thread, lael.
I'm onto my fourth batch of yog, made quite a nice batch as suggested by Florian with just with long life full cream milk plus full cream milk powder and a tub of Coles own brand plain yog as the culture.
However my absolute best results so far are my latest batch.
Manning Valley Farmers unhomogenised milk plus a good dose of Aldi full cream milk powder and a kilo tub of Aldi "Just Organic" plain yog to make six kilo tubs, in the Crown Urn at 40 degrees. I note that the Aldi stuff has acidophilus as well as a number of other strains, whilst the Bornhoffen only mentions thermophilic strains such as Strep. Therm. Pity they lost the plot and sold out to industrial strains. As mentioned, Bornhoffen used to be called Bornhoffen Acidophilus but no more.
Really rich and almost like a cream cheese, and so much yummy butterfat that the tops of the tubs are covered with a thin disc of cruncy cultured butter. Also it's not eye watering sour, very well balanced.
Using a whole tub of Aldi is good value as it gets me an extra plastic bottle for batches, to give away or reuse, and it doesn't bump the cost up much when split among six kilos.