This is how we recently set up our non-freestanding tunnel tent (Wilderness Equipment Second Arrow), on the platforms at Wild Dog Creek in the Walls.
I cut a short length of guy cord (from spare carried) to secure the tail end to the chain that runs around the outside of the platform. The wire guys on the platform were used to secure four of the main anchor points. The rocks (already there) were used for additional anchorage and tension. Also secured the four guy ropes on the tent to the platform chain. No pegs were used.
It had me puzzled when I first saw it; a bit of fiddling around got it sorted. Held up no problems, through some reasonably strong wind at times. I can't recall if the Overland platforms are different, as we mainly used huts on that trip. The ones in the photo below have chicken wire underneath the boards, to help prevent objects from falling through the gaps.
I stumbled upon some very thin poly foam in a hardware store near work before Christmas. Maybe only 1-2mm thick and weighed almost nothing. I cut two sheets roughly the size of our sleeping mats. We used these underneath the mats for extra insulation. This seemed to work well, as we weren't cold inside the tent at all. Even through cold winds, rain and snow.
- Tent Platform Setup Wild Dog Creek