The two back straps need some fixing points which I’m working out. For now they are held through the rear hoop holes.
There should be a pair of staples the same as the ones you will have fitted to the shark tooth rail which mount to the rear capping panel above the anti-loose catch (in your previous pic you can see the pair of rives which get replaced by the staple)
You can see what I mean in these adverts:
Link 1
Link 2
I can take some more detailed pictures of mine this evening if you need.