Embedding custom Icon-File into a .vssm Stencil Document?

[Master E]

Well Hello,

I have a stencil with some custom master shapes, including the VBA code to make them do their supposed work. This also includs a VBA-Code that generates and adds a custom ribbon to Visio upon opening the stencils. Works all pretty nice with icons taken from build in library. 

What I would like to do is to embed a custom-icon (in any format) into the stencil file so I the internal ribbon can use it as a resource or similar without the need to copy an external file additionally to the stencil file.

The "custom-ui" tool allows to embed an icon/picture into the file-structure of the .vssm-Stencil document, but opening the stencil-File with Visio and resaving it (e.g. after changing some detail on a Master-shape) will completely delete the custom-UI Folders/Files out of the file. So that is not an option.

Also, simply manually copying a .png into the .vssm file (e.g. with 7-Zip) will only break the Visio-stencil. I suppose I need to register such a resource in the xml structure of the .vssm file but I could not find any information on how to do that, nor do I now if such an approach would persist a change made inside Visio.

Does anyone have an idea regarding this problem?

[JuneTheSecond]

Thomas Winkel has submitted a great work at User Submitted Stuff.
http://visguy.com/vgforum/index.php?topic=7134.0

How would you like his work?