XStacks stacks should reside at the same level as the document. A XStack stack is merely a stack that is named with the name of its associated document with a "¥X" extension where "X" is a number from 0 to 999. By placing "¥0" in your document at the start of a Page, Waldo will create a XSTack Button as it loads the file. When the reader clicks on the Button the stack will be displayed. There may be as many XStack stacks associated with a given document as there are Pages in that document.