Thanks to all for the tyre pressure and sand driving tips. We were able to go everywhere we wanted without getting stuck or breaking a tyre bead once.
I was airing down to 30psi for hard packed tracks/corrugations and 18-20 for soft sand.
We did fail to proceed up one dune at Steep Point, dropped pressures to 16psi, backed up a bit further and she got to the top no problem although I was holding it in a low gear at around 4500rpm for most of it. At the top we aired back up to 18psi and didn't go lower for the rest of the trip.
The corrugations into Steep Point were just awful, that was a long and mentally challenging drive. I normally don't like to abuse my cars like that. Nothing broke or fell off but our food tub did wear though the leather on a rear door trim
Crossed that one off the list, no need to go back!
Porsche did great on the trip, zero issues over the 5050km travelled. I bought a heap of "just in case" stuff that didn't get used, but you gotta carry it...
Snatch strap etc
20lt spare fuel
Compressor did get a workout and I had to use octane booster on 2 occasions. No check engine lights although my check liver light did come on a couple of times
No real hard tracks done (compared to Vic High Country) but lots of gravel/rocky/sandy stuff which the Cayenne excelled at.
Mt Nameless in Tom Price was probably the most technically challenging, then Steep Point and Ningaloo access for soft sand and corro's. Rocky entry to Cable Beach was fun too.