Thanks for all the help folks.
I've come to the conclusion the problem all along has been supermarket milk. I finally found a good source of raw cow's milk (someone has a herd of Jerseys 2 miles from my house!) and what a difference! I made a manchego like cheese Saturday and last night I made a camembert. The set on the curds is totally different with raw, grass fed cow's milk. I'll try another batch of St. Marcellin once the camembert moves to the wrapping stage. At this rate I'm going to need to get a bigger cave!
I'm never using store bought milk again! Adding CaCl and lipase is a poor substitute for the real thing.
Now to find local goat's milk...