"In the steps under question we are straight and at the same time backing the LOD."
If you had a real teacher, you would know that it is the foot which is backing LOD. The body should still be quite underturned.
"You said that there is no information regarding the direction of the steps
I must be mistaken when it says back down the LOD."
"Backing LOD is not a direction of movement"
Backwards is.
The book gives you two seperate pieces of information - direction of movement of the foot relative to the standing foot. And direction of orientation of the moving foot.
In contrast it gives you only some vague clues about the orientation of the body - most of which do not match what actual dancers who win competitions do or teach.
"Do you back diagonal to the centre then. Or is it diagonal to the wall."
On a reverse turn, yes, the BODY would be underturned and partially backing DW, while the FOOT would be backing DC. That's just the way it's done.
Check the preface to your book - it will tell you that the alignments given are FOOT ALIGNMENTS.