expression.Gap
expression Required. An expression that returns one of the objects in the Applies To list.
Remarks
Numeric values are evaluated in points; strings can be in any units supported by Microsoft Publisher (for example, "2.5 in").
Example
This example sets the distance between the callout line and the text bounding box to 3 points for the first shape in the active publication. For the example to work, the shape must be a callout.
ActiveDocument.Pages(1).Shapes(1).Callout.Gap = 3