list_open_image_field
The name of the field in the listname working list that contains a tree item's image path and file name, relative to the images directory, that represents an expanded node. Leave blank if using default images.
Default value
Blank. Default images are used.
Valid values
The name of a valid field, in single quotes. A list of fields in the listname working list can be chosen from by clicking the corresponding dropdown button in the property sheet.