To enable the frequent release of new features within Muse, the team is always simultaneously working on many different improvements only some of which are completed and exposed in any given release. In the 2014.1 update some of the underlying code related to SVG support was unintentionally enabled. When copying and pasting from some versions of Adobe Illustrator (and other sources) the result may be an SVG vector graphic in Muse, rather than an image. While the SVG may appear to work in Design view, it can cause failures when exporting or publishing from Muse. This functionality will be disabled in an imminent dot release, 2014.1.1. We advise users to remove SVG content from their sites. Until 2014.1.1 is available, the graphics will need to be brought into Muse as .png, .jpg, .gif or .psd images using File > Place or Import, rather than Copy/Paste.
Sorry for the inconvenience. SVG support will be fully implemented, tested and included in a future major update of Muse.