Locked Stack Error Message

[Rob Cozens]

Hi All,

Scenario:

*  Group with one image & one field, image in lower layer.

*  Replace image with a new image, now in upper layer.

Problem:  The Application Overview will not let me change the layer 
numbers of the image & field (buttons are disabled).  "set the layer 
of image ..." from the message box returns "Stack is locked."

I have done nothing to explicitly lock this stack, and the stack's 
cantModify property is false.

Where/how is the stack locked, and how do I unlock it?
-- 

Rob Cozens
CCW, Serendipity Software Company
http://www.oenolog.com/who.htm

"And I, which was two fooles, do so grow three;
Who are a little wise, the best fooles bee."

from "The Triple Foole" by John Donne (1572-1631)