Sorry to see that you took my advice the wrong way.
I was not aware that you already posted on vb.com. A simple question as what the meaning/use of a function/variable inside ImpEx does, can be answered on vB.com without being directed to vB.org. If you would ask for help with modifying ImpEx, then vB.org should be the place to ask.
This thread is 2 years old, in the mean time there have been many changes in vBulletin, ImpEx and probably even the source system. This makes any information in this thread at least outdated, if it is still correct at all. Jerry is the developer of ImpEx, and as Brad already explained, he hardly ever visits vB.org, so it is not very likely that you will find your answer here.
My response was simply an attempt to point you to the place where you would most likley get the answer to your question the fastest.