Gave that a go, in fact i think i tried all 24 Permutations and two different stepper motors last nght (but it was very late so i may have missed one or two)
Basically you want the coil energized in the forward or reverse direction or not at all. I am not sure what the library does but I am not surprised you can't get it to work. Try driving the pattern by hand,
see http://www.thebox.myzen.co.uk/Workshop/Motors_4.html for the three patterns you could use.
think it must have been a trouble with the IC, switched it out and run as a two pin set up with a couple of npn transistors and the motor is stepping fine now.