QTR-Quadtone RIP

I'm trying to design my first QTR curves and I have some basic questions
I hope someone can answer.

1. When I print out the calibration page to determine the default ink limit,
should I then print it again with the new limit set before determining
relative densities? The calibration tutorial in the QTR release doesn't
mention this, but Tom Moore says to do it in his user guide.

2. I'm confused by the explanations in both the calibration tutorial and
the Tom Moore guide about how to choose the ink limit. In my case, the
limit values for the black ink was near 90%, but it was at 100% for the
lighter inks. Should I have chosen 90 or 100? What exactly is this default
limit doing? And why not just set it to some arbitrary value and set the
limits for each ink individually (which is what I actually did).

3. When I printed the 21-step target to perform the linearization, the
density at 100% was less than the density I'd obtained on the calibration
page (down from 1.65 to 1.59 -- this is on EEM, so these numbers do
seem reasonable). What caused this? I guessed that it might be the gray
overlap, so I set that value to zero, and it seemed to fix the problem. Was
that the right thing to do?

4. When I come to do the actual printing, should I be using an ICC profile?
I assumed not since I've linearized. If I now make curves for different
tonalities and set up a particular mixture I like, is that the point to create
an ICC profile with CreateICC and to use that?

5. The QTR manual shows a page setup feature for overcoming the
infamous Epson centering problem, which I have on my 2200. But the
feature didn't appear for me. Does that mean I have not fully installed
QTR? Or has that feature gone in 2.5? Or isn't available for the 2200?

Any comments or advice would be much appreciated!

--Daniel