I found the mistake. there are problems with embedded picture elements in text frames when they are invisible in single breakpoint. unfortunately I have no solution for it.
would you mind sharing your .muse file with us so that we can investigate and try fixing it?
For sharing the file you can follow the steps explained here - https://forums.adobe.com/docs/DOC-8652 and send the link to me in a private message.
For doing a private message hover the mouse on my picture and click "message".