I love this name. It looks so ethnically German, which I love. I love the pronunciation, it is also very unique. I picture a beautiful German girl or woman with blonde hair and blue eyes. Karolina is pronounced Care-uh-lee-nuh.
I knew a girl named Karolina in my first year of high-school and she said that in Poland it's pronounced like Caroline and she gets mad when people pronounce it with a at the end.