Have you done all the updates for your machine? Many times the updates take care of the issue. These are free downloads from the BL web site and specific to your machine. These are not "upgrades" which have fees. It is easy to send to the usb and then load into machine. Just follow the steps as directed in specific order.
Does your machine have preference pages where you can change settings?
There should be no issues with using the thread cutter. I have used them all 3 machines and no problems. I don't use if using the monopoly threads.