Another thing to check will be the height of the take-up rail. You should be able to slide your fingers between the rolled up quilt and the bed of the machine but touch both on the way through. I have the Pfaff version of this machine and had quite a learning curve. Consistent speed is a must as others have pointed out. Enjoy your new machine. If I can help send me a pm and I'll be glad to offer whatever knowledge I have picked up.
Darren