Many thanks for all the great links Eric.
The lacing went well - it's challenging as the holes between the wooden parts are all internal. I laced them with the wooden parts slightly apart, about an inch gap, so I could help feed through the double strand (some of the holes weren't perfectly smooth inside, making the strand catch sometimes). It didnt seem to matter which hole I started with, it still seemed to end up eventually with the square (ie. I was initially concerned about what order to go through the holes as I didnt want to have to go back over the same section on the underside thereby doubling the thickness, but this never seemed to eventuate fortunately). Once I had all four sides of the 'square' laced, finishing by going through the loop at the end of the double strand, I could pull the lacing tight bit by bit, and then put the wood parts in their proper location and finish the tightening and tie it off. Then we laced the central diamond section to tighten the 'square' with a slightly thicker diameter strand. Patience is the key!
Thank you all,
Suzi S