Most likely, your Mac isn't recognizing the cutter for what it is. In the Cut Settings window in SCAL5, if you click on Test Connection, does the cutting head move?
Also, did you verify the Baud Rate between SCAL (click on the Settings buttons in that Cut Settings window) with what your cutter requires or has set? A mismatch will cause the cutter to do nothing... not respond.
If the Baud Rate is for sure not the issue, you'll need to research your cutter's driver requirements and see if you need to install something on your new Mac in order to have cutter recognized. It was my understanding that USB connected cutters would not have an issue with the latest Big Sur O/S updates. But who knows.
