I also had the whole series many years ago, and remember writing to them on the very subject of how much wool to buy as the particular pattern only said a certain number of balls, no weight or ply specified. I received a dismissive letter back, totally disregarding the fact that THEY were in the wrong and suggesting that I would simply need to buy more balls if the yarn was only available in smaller quantities. Totally useless! I think I ended up working out the ply from the tension square details, and went to my local yarn shop. They would always take back unused balls of wool, provided they were brought back in good time. I'm talking yonks ago, does such a place still exist? The book collection eventually ended up at Oxfam.
However, to add insult to injury, I bought a shawl pattern from a certain well known auction website, and it turned out to be a photocopy from the collection (this time with appropriate yarn details) - you live and learn. Brigitte, you might be sitting on a goldmine.