[RarlyL8]

I thought someone would chime in by now. I will try to answer some of your questions.
The BOV bypasses the throttle during closed throttle events. This prevents the rotating turbo from pounding the system with pressure pulses while winding down.
The C2T uses a long neck intercooler and a stand-alone BOV. The large assembly of the 930 is eliminated. You can reproduce this with your engine. Porsche needed to sell as many 930 engines as possible to maximize R&D costs, one reason they stayed the same for so many years.
The boost pressure switch cuts off the pumps at ~1.1Bar. That is why it is marginal to run a 1.0Bar spring with a stock switch. Any leaks and the switch becomes over sensitive due to a faulse signal.
I'm not familiar with the fuel enrichment relay. The WUR governs the mixture beyond the static set of the fuel head. The cold start valve is electricly innervated and timed during cold start events.