I've emailed with Susan Druding of About.com fame. She's been incredibly helpful. Based on my initial thoughts and her invaluabe input, this is my current game plan:
I’ve managed to size the template using Photoshop, now it’s just a bit crooked. I’ll redraw it and then I’ll decide whether to just tack through it in order to trace it with tread or to cut it up and trace around the edges with coloured pencil. We shall see.
In the larger areas, I’ll just do a swirly design, I think. Or I’ll appliqué scraps taken from the cut-off of the border fabric. I’ve got elephants and jewels to choose from. Another “we shall see”.