Michal, I understand where you are coming from but I am very careful about any suggestion of reverse engineering of Xara's code.
The XWR schema is different as I am not altering any compiled code, just using the known capability of the XML Tagging as above.
The internal Xara widgets all come with a number of codewords saved in the Names Gallery. Some things like WTag:image:lastdark is associated with the hidden Jump Last icon so you might be able to use another graphic and add that name to it.
Elswhere WTags can control the scale of an image.
There is no documentation for any of these so anything I have have been done through experimentation. Resizing images dimensions have been about it.
Acorn
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