Dave,
After reading over the description of these motors on the RS website, I believe these 4-phase motors are standard bifilar wound stepper motors with 6 or 8 wires. The 440-420 has a 6 wires and can be wired as described in the MID user manual. The 191-8328 has 8 wires which likely can be wired in series or in parallel. The series configurataion will favor high torque, low speed operation, while parallel wiring should provide better high speed performance. These motors should be compatible with the MID series drives.
Regards,
Brent Runnels
Applications Engineer
National Instruments