We don't document those because they can and do change between versions.
You can take a look at the Actions and Events sections in the ShapeSheet for
the solution shapes to see how the solution uses the Add-on. As noted above,
it is possible that these arguments will change across releases or even
service packs, so you do want to be careful about using them.
--
Bill Morein
Office Graphics - Visio
Microsoft Corporation
http://blogs.msdn.com/wmorein
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