The knack (which I do not pretent to have grasped) is being able to freely and consistantly move the quilt on the flatbed with your hands whilst maintaining a constant speed with the needle.
Bilbo has given me a couple of excellent pointers over the phone earlier today, and the sites that Joanna recommends are very useful indeed - thank you, girls.
Don't think for a moment that I am giving up with this, but the way forward for the Spring Garden Trellis quilt (which is all sandwiched together and stuck with spray-baste) is to follow my template with the normal 'foot' arrangement.
I should be able to follow the curves without too much difficulty (I hope!) - and I really don't want to have come this far just to cock up at the final hurdle.
I'll leave more ambitious free quilting for when I have (a) a proper free action foot which does not look to be expensive on Amazon and (b) more experience with needle control.