Hi David. I'm not familiar with the Walker Touring Plus but it goes together much the same as other Chalet type awnings. As you say, the main differences are the type of roof fixing for the apex and roof side rails to the van.
The lugs IF used for the WALKER are as follows and they should be screwed in along the awning rail, the Foorman's loop in the centre and two awning mounting brackets, 1 each end and equispaced about the footman's loop. There is a short vertical pole with a flattened end that fits into the footman's loop and holds the end of the roof bar while the two mounting brackets each hold one hook ended side rail.
Footmans loop.jpg - Bild entfernt (keine Rechte)awning pole mounting bracket.jpg - Bild entfernt (keine Rechte)
Randa