Running a stepper motor & hardware Serial simultaneously

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5

I think you're supposed to use another serial com port. Serial (with an uppercase S) is already used for communication.
Try:

// Include the necessary libraries
#include <SoftwareSerial.h>

#include “RoboClaw.h”

// Create the serial communications object
SoftwareSerial serial = SoftwareSerial(SoftRx,SoftTx);  // serial with lowercase "s"

// Create the RoboClaw object
RoboClaw roboclaw = RoboClaw(&serial,10000);  // serial with lowercase "s"

// Start communicating with the RoboClaw hardware
roboclaw.begin(38400); // This baudrate should match the one set via BasicMicro Motion Studio.