<-Found my copy. It's not actually all that detailed, although the overview it gives is excellent (and it's sumptuously illustrated, as well it might be for £30/C$75/US$60). What's probably most useful for us is the book's references, two of which bear further research:

 Philip Longworth The Unending Vigil: A History of the Commonwealth War Graves Commission, Barnsely (Leo Cooper) 1985
 Edwin Gibson and G Kingsley Ward Courage Remembered: The Story Behind the Construction and Maintenance of the Commonwealth's Military Cemeteries and Memorials of the Wars 1914-1918 and 1939-1945 London (HMSO) 1995

I'll scout round for some ISBNs for these. REDVERS