I just find in the same situation since last month i gott the same printer machine and the same board.
Wait a week and i will try to figure it out.
Should be not to dificult to use it.
You are planing to use the motor wich came pluged to the board?
I didnt like it too mach. May be i will look to set up for more powerfull motors.
The schematic of a2918 suggest a peak current of 1.5 amps, and that should be enough for good torke results.
See you next week.