This door has had an interesting past. It sits in a doorway in a big old house in rural Aberdeenshire. The design appears influenced by a suite of stairway windows in Mar Lodge (below), the NTS property near Braemar.
The wing of the house in which the door is located was destroyed by fire in the 1930's, and subsequently rebuilt. I suspect this window is a remake of an original, because the leading varies slightly from another, clearly older panel with a similar design. When it was remade, 3/16" lead was used and, as a result, the panel had simply stretched over the years.
We removed the panel, replaced the thinner lead with 1/4" and releaded, adding extra tie wires to provide additional support.