Have you used this design before? Sometimes designs aren't perfect and it doesn't make any difference if it's a freebie or purchased. So maybe this is the problem and not your machine. Hopefully you'll et it straightened out and get back to your sewing.
I would clean the bobbin area, re-thread the machine and try a new needle. Also try slowing the machine down a little . Hope this helps .
I was told by Bernina dealer to always thread all machines with the foot up but thread the needle with the foot down.