What kind of system should I use?

If you only have one serial (COM) port, you should select the system belonging to the type: [Legacy]. But if you have two or more serial ports, just select the corresponding type.

If you only have one serial (COM) port, each actuator ID should be different (typical values are 0 and 1). If you have more than one serial (COM) port, the typical actuator ID is 0.