I am trying to keep a good attitude, but these questions have all been answered and explained within the first few posts of this thread.
It is summed up very well (and with pretty pictures
) in the Cine4Home review of the autocal software (not surprisingly, linked in the first post of this thread
). But since it presents such a challenge for folks to do any manner of detailed research on their own, I'll provide the Cliff's Notes version.
You will roughly center the shadow of the meter on your screen/projection surface, while also making the meter (as shown in the JVC software close to the RIGHT SIDE of the target box.
Further to this, you will also want to ensure you meter's sensor is set up parallel to the light path by making it's reflection (should be a bright, circular spot) sit directly above or below (not directly back into) the PJ lens.
For maximum accuracy, you will want to move your meter so that both these above situations exist BEFORE EVERY RUN.
Many times folks are making the adjustments via the Picure Mode Settings screen, which immediately follows the above screen and precedes the below screen.
I think this is a poor idea because most changes that are made would have an impact on brightness (in some form or another) and would thus would change the location of the meter within the target box (as shown above). Sure there is always the option to use the "back" arrow to verify and readjust, but with the impatience that abounds, I'm not sure anyone would be that vigilant.
My preference is to set these via the PJ menu PRIOR to starting a run:
To ensure you are not missing any crucial components of the calibration run, be sure to look at the data that is presented at the beginning of the process: