Welcome, Bill.
I'll take a stab at some of your questions. No doubt others will jump in and
correct me. :)

> What is the difference in the 4 port and 6 port Renesis, and why should I
> choose the one that I should choose?
I believe the 4 port has slightly less power, but is easier to make an
intake for.

> What does P Port mean and how is it different from the normal port?
P = Peripheral, as in at the edge. This is a modification people make to the
port to provide more power (but a less smooth idle). Bruce Turrentine (the
engine builder guy listed on Tracy's web site) could advise you on this.

> pretty well figured out by you guys...Intake, Exhaust, EC2, Etc..  Some
> other things, cooling for oil and water, still being invented but
> with some idea of what to do.
Agreed.

> how to run gas from the tank to the engine and back, are still being
debated
Obviously Paul's demise has led to discussion. Unfortunately because of the
high fuel pressure, flow and the required return there's really no "right"
way to do the fuel system. It's different on high & low wing, and there are
many ways to approach it, each with its own advantages and disadvantages

> How many different CORRECT ways to do it are there?  Is the fuel system
for the
> rotary totally different from a REAL airplane engine?
Lots! There are quite a few different variations flying with no problems.
Yes, it IS different from standard airplane engines.

What'cha mean "real"?  Them's fighting words around these parts. :)
Regards,
John