One of the Kendo UI Editor design goals is to clean up formatting so that it matches the content of your site -- so the loss of formatting is likely to happen when pasting within it. The issue with the image has two probable causes: either the pasted content has some styles that break the page layout, or the page itself has styles that change the image. With only the video, my best guess is that the image has a CSS float:left applied, thus the other content is positioned next to it. This may be resolved by applying a "clear fix" to the container in which you render the content. If this recommendation does not help, please provide some way for us to reproduce the problem -- for example the content that is provided to the paste handler or a page that shows the rendered content.
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