InlineUIContainer's Height and Width can be changed dynamically. However, the changes are visible when the layout of the RadRichTextBox is updated. The layout is updated automatically when you scroll RadRichTextBox, resize the window, start typing in the document, etc. You can also force the update as follows:
As for your other questions, please refer to the other forum thread
in which you have posted this issue.
the Telerik team
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