Moving Prius from USA to Europe/Spain

Hej to all clever Prius owners and Happy New Year! I own a 2004 Prius, since it was new. I have been happy happy happy throughout and made a mistake of brining my beauty to Barcelona, Spain in September of 2018. There has been nothing but trouble since, and getting worse.
Nothing is that same in a US car as inEurope, it turns out. I had to add fog lights, change all the light fixtures and covers and then they said the car is too heavy to carry 5 passengers... We managed to cross all these hurdles with patience and a bit of empttying and then putting back some items in the car - for the second weigh -in.
Then started the real nightmare...I went to buy a CD with Europe instead of the US for the built in GPS. At a Toyota dealership. They took out the CD (first time ever removed), and when awe came to put the new CD in , it got stuck. I was charged 400 Euroes to fix the broken (by them) CD player eject button, and once fixed, the dealership said - oh, the format is different... I had of course asked if format mattered and if it was going to work the first time I went to the dealership, to order the new CD!..
During the process of repairing the CD player, the car had the warning triangle on, and when we asked - the dealership said "don't worry, its just on because parts of the electric system is detached with the CD player". We kept driving and the car atarted acting strange, loosing power, but unevenly. I took it back fro diagnostics and was told 2 cells (8&9) in the (just refurbished!) battery were blown. Learned that this happens when the Voltage surges.
My question, and pardon the long story to get here, is - did this happen wheel part pdf the electrical system was unplugged while they were fixing the CD player?
This dealership is not helpful and has lots of angry clients, so I need to have proper ammunition when I go back with this theory.
Right before we took the car in, we had a day trip up the coast, about 2 hours each direction with no problems.

Also, where do I turn for higher up Toyota help? There must be a higher place to go?

Than you!