What makes me kind of angry is how quickly the quilter is blamed for the issue, when it's a well known fact by now that there is a major problem with the BSR skipping stitches (not creating long stitches but actually skipping the stitch. Needle goes down but does not form a stitch, often several in a row). If you do a Google search there are tons and tons of people writing about the same problem. You can quilt all day long on a plain fabric sandwich (no seams) and the BSR won't skip. Put it on a real quilt sandwich and you get skipping. The new, heavier spring will help some but it won't completely solve the problem most likely.
I highly suggest you contact your dealer and ask about getting the new spring installed. Depending on when your machine was last serviced, there may be updates for both the machine and BSR that your tech can do as well. If all else fails take the machine and your quilt up to your dealers and show them what it's doing. I'm in the process of having to do this myself.