It seems like the Christmas tree light problem is solved right in time for Christmas. We've had the lights shine since early this morning, so yesterdays shopping and Mathias handy work in the evening looks to be successful. This is how "fancy" our new electrical connection for our Christmas tree looks:
Two 100W transformers, two travel plugs in order to go from a US outlet (on the transformers) to Swedish outlets and then a converter to get back to a US plug. Looks ugly but it works and it's hiding behind the tree and the bookcases. 🙂
Merry Christmas everyone!