All models have a basic rating of 3, with extra stats added accordingly. For Havok you need to count 1 as equaling 0, 2 as equaling 1 and so on. So you come out with (N-1) * modifier. So, for example, the Karn Trooper has: 1 Speed, 1 Firepower, 1 Close Combat, 1 Psyke, 2 Strength, 2 Armour and 10 Battle Rating. Put this into the above and you get: 1 Strength + 1 Armour + 3 = 10. For instances of -1 you subtract from the total. So the Stats are: 2 = Speed 4 = Firepower 2 = Close Combat 2 = Psyke 3 = Strength 4 = Armour