According to MyDealz in Germany, you could get Gold with just two double transfer round trips from Frankfurt to Umea. Each round trip would have to transit both Copenhagen and Stockholm, which would give 12 x 4 = 48 sectors. Flight changes and cancellations could, of course, screw up the best laid plans. It seems, to maximise the offer, that new Eurobonus members (such as myself) should sign up just before taking the flights. There are lots of other flight combinations and destinations, obviously.