The Wicked Device Motor Shield is designed for use with bipolar rather than unipolar stepping motors. However, some unipolar stepping motors can be wired as bipolar units so long as the center taps of the two sets of windings are not connected.
The user's manual for the motor shield shows three different wirings for stepper motors. It should be mentioned that the 6-wire unipolar motor can be used as a 4-wire bipolar motor by simply leaving the center taps (5 and 6) unconnected.
The 5-wire unipolar configuration is used by the 28BYJ-48. Since this configuration has the center taps connected to each other, it does not seem suitable for use with this board.
There are a number of ways in which stepper motors can be wired. One article discussing the various schemes can be found here. This article discusses the differences between unipolar and bipolar stepper motors, but may require some additional resources in order to understand it further.