To clarify things that are being misinterpreted, I experimented and have my example of how to do it.  This was run on a V130 with the latest firmware.  It is the basics of everything you would need, and really is very simple once I got there.  It gives the "immediate" flow rate between the last sense and the one before that, like I have previously suggested.  I used the 2.5ms count for simplicity and the ability to run on older units.  Edit: oops, wrong number in the vlp, changed it to correct.