Cropping with prostitcher premium

i am working on a quilt with  appliqués across the entire quilt (long flower stems and large petals).  I am quilting block by block and cropping out the appliqué.  Because some of the stitch spaces are small, small fragments of the quilt design are left.  It seems that whenever the starts and stops are very closely clustered the machine will drift off to the belly bar and will shut down the machine if I don’t pause it before it hits the bar.  Has anyone else experienced this or found a solution? I have found some workarounds, but it has been very time consuming.