This kind of question has been asked a million times. The short answer is that instructables needs to check the laws of each and every country, one by one, to allow contests which means that the list of approved countries keeps growing. Dont worry! They will get to Sweden but haven't just yet. In the mean time you ARE allowed to participate you just cannot ship the prizes directly to Sweden at this time so either participate and forfeit your prize (if you win) or have it delivered to a friend in one of the countries on the list..