2.1.615 Part 1 Section 18.3.1.34, dialogsheet (Dialog Sheet)

a.   The standard states that the drawing element is specified in CT_Dialogsheet.

Office never saves the drawing element.

b.   The standard states that the minOccurs value for the legacyDrawing child element is 0.

Excel requires an occurrence of this element.

c.   The standard specifies that the drawingHF element is a valid child element of the dialogsheet element.

Excel ignores the drawingHF element.