You can use the Property inspector to edit tables.
Left aligns the table to the left of other elements (so that text in the same paragraph wraps around the table to the right); Right aligns the table to the right of other elements (with text wrapping around it to the left); and Center centers the table (with text appearing above and/or below the table). Default indicates that the browser should use its default alignment.
If you entered a value in a text box, press Tab or Enter (Windows) or Return (Macintosh) to apply the value.