I don't see how the rinse cycle will manage to remove all the stuck on build up and varnish... The Auto-RX rep in the email said the same thing, so i'll give the rinse cycle a shot and take the valve cover off again and check out the results.
Actually, this is what the rep said in your email posted above:
a better clear indicator would be after finishing the rinse phase.
Here's an analogy (note - this is written in the spirit of good-natured fun):
"Boo, this frozen pizza sucks! It didn't work! I put it in the oven for
half the time the instructions said to, and it's still frozen! I'm going to complain on the internet."
Wait until it's done, then bash away.