Is a class action lawsuit even possible with regards to where the company is based?
Very much so. But I doubt a class action is five customers suing the company.
The EU is actually committed to offer class action type redress for consumers and if I remember correctly somewhere in the documents below it lists Sweden as a country that already has a class action system in place.
http://ec.europa.eu/consumers/solving_consumer_disputes/judicial_redress/index_en.htmLet me know if you find anything interesting in there.