long enough to cause the power to be cut to the radio or a guick pull of the radio fuse will resurrect the radio. I was told there is a software update for this problem.
But in my 08 Cayman S the radio started acting up, like not working, then working with no pattern, and I had the car in and the tech reset the radio. But the 'fix' didn't take or last long. I took the car in again (different dealer more handy than the dealer where I bought the car) and this time the tech also reset the radio but found the radio did not reset properly, or perhaps let the car sit a while then checked the radio again, and the radio was replaced under warranty.
There are alot of fuses because there are a lot of different circuits to protect. IIRC one row of fuses (the bottom row) are spares.
As for the new HPFP it may be defective (out of the box) but the car should be subjected to some kind of shake down test while at the dealer before you pick up the car to at least verify HPFP works out of the box. This does not mean the pump can't fail a mile away from the dealer after you pick up the car. But the odds are slim. Remember there are alot of cars out there that have not experienced a HPFP failure at all, let let alone a failure of the replacement HPFP.
If you are worried carry the bad HPFP in the car. The odds of the car having two bad HPFPs at the same time has to be astronomical! (Insert smiley here!)
Sincerely,
MarcW.