This is a wonderful collection of pictures. It shows how much some of the town has changed, and also how recognisable many of the streets still are, paticularly Main Street, which with the exception of the demolition of the Wide Close and the building of Longrow South remains architecturally relatively unchanged .
So far as the location of the Mill is concerned, having seen some of these mill photos before and in the past heard older generations talking about the place, it was located at the present junction of Mill Street and Lady Mary Row.and the Mill Lade came through what is now Millers Park. The burn which fed the Mill Dam ran along the fields near Hillside Road and is now culverted from a point near to the two blocks of flats on the North side of Hillside Road right down to the loch. I believe this culvert runs along the South side of Lady Mary Row beside the Tesco building and exits near the War Memorial.
These photos at the Mill would appear to have been taken at the present site of Lady Mary Row looking towards the direction of Mllers Park.
This link to an 1865 map of the town shows the Town Mill:
http://maps.nls.uk/townplans/campbelton.html