@sallyember: This might be yet another Smashwords Meatgrinder bug, or you didn't follow the Smashwords style guide to the letter and applied direct formatting to text (i.e., without applying a style). In order to fix these error messages you'll need to find out where they occur and what caused them.
Try the following:
- Download the converted ePub from Smashwords.
- Download and install Calibre (freeware).
- Open Calibre and drag & drop your book to the main Calibre window.
- Right-click the book and select Edit book from the menu.
- Click Run check.
- Click on an error message to display the code that causes the problem and post it here.