Stir the grape pack down into the must twice a day. Just before you rack the first time, hand squeeze the grape pack to get all the juice out of it, then discard the grape pack.
If you follow the instructions, which come with the enzyme, it is NOT likely you will have any problems getting it to work properly.
I have lots of experience with this enzyme and the milky film it may or may not cause, because I didn't use it properly the first time. After you rack, add the enzyme as instructed. Make sure the enzyme is stirred in really well and leave it in the wine for the proper length of time (days).
The idea here is to add the enzyme AFTER the bentonite has been racked off, as bentonite will totally deactivate the enzyme. So, when racking before adding the enzyme, make sure you leave behind as much sediment as possible, because the sediment will be loaded with bentonite.
On the racking AFTER ADDING THE CLARIFIERS, you might see a milky film, which looks like thin cake frosting, that runs down the inside of the carboy. If you do, call George and get further instructions.
I am one of the very few wine makers, who had trouble getting the enzyme to work properly. Before adding the enzyme, I believe I racked over too much of the sediment, which brought over a lot of bentonite.
After clearing, I finally got rid of the milky substance by adding a half teaspoon of bentonite, stirred it in very well, let it set for a couple days, then used Superclear to clarify again. I would talk to George before you try this, though.