Rob the NZ Ordnance Staff at Mulheim picture and the John MacVean Walker picture are well known to me.
The Mulheim picture is especially interesting due to the badges worn by this chap.
In the Mulheim picture there are 13 NZAOC cap badges, 11 Artillery cap badges, 2 NZMC cap badges, 1 NZMGC cap badge, 6 various infantry Regiment cap badges, and oddly some British soldier has got himself into the picture.
The two officers on the left appear to be Main Body men from their service stripes, but most interesting to see the officers are wearing standard brass badges instead of bronze officer badges.
The Staff officer with the blue gorget collar patches interestingly is not wearing any service stripes.