That is appalling treatment.
I assume since you are driving that far that there is no where else you can take the car.
I would start by documenting every instance of abuse, and then sending that document to the higher headquarters in your area. If that gets no action, I would continue to move it up the chain until I got satisfaction.
That kind of treatment is unacceptable even if you purchased a 12K car from Nissan, much less a Porsche.
Frankly, I’m a bit stubborn, and would never let that kind of treatment go unanswered. I also realize that it is time consuming, and takes a mean streak most people don’t have (to their credit).
Good luck

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Just sold my beautiful CS, now the fun begins as I look for its open top replacement...