If you are wondering how to get a shape's id, then this article is for you!
What's My Shape's ID? (http://www.visguy.com/2009/07/15/whats-my-shapes-id/)
If you are answering a Visio development-related question that involves cross-sheet references in the ShapeSheet, then you'll want to refer to this article as well!
To link to these articles, I've provided BBCode and HTML syntax to make it easier. Just cut and paste one of the following, depending on where you are referencing from:
BB Code:
[url=http://www.visguy.com/2009/07/15/whats-my-shapes-id/]What's My Shape's ID?[/url]
Html anchor:
<a href="http://www.visguy.com/2009/07/15/whats-my-shapes-id/">What's My Shape's ID?</a>