Sorry no it's absolutely not about self gratification
Neil you have taken possession of your flat/apartment, they offered you a price you accepted, you had a problem with the first unit they exchanged. They gave you parking spaces which you are not happy with. Do you have separate Umowa's for the parking space and the flat?
If the answer is yes then you have an issue with the one contract for the parking spaces - if the answer is you only have one Umowa then you have an issue with the purchase of the flat and parking space. You must have used a lawyer in the purchase or someone translated the documents for you. Have you signed the notarial act? Did you not have a sworn translator.
I am British Neil and I learned many years ago in Poland spoken words mean NOTHING it is all about the written contract and written correspondence. Unless of course you have recorded all of your meetings with the developers representative. You have to accept you did not know the rules - learn from your mistakes we have all been there in Poland, you are not alone on this one. British rules do not apply in Poland and vis a vis. Ask yourself a question - why do the Polish migrants adore the UK and Ireland Simple answer because it is easy and they do not have to struggle or fight the system. Poland is not the same my friend.