From Webstyle, select web pages and select a theme you wish to use.
Edit the page as required prior to saving it.
Then select another layout within the same theme. After selecting the layout, a 'copy theme' dialog will be displayed. This lets you apply the last saved NavBar and logo to the current layout.
When you save this page, the NavBar and logo will be referenced from the same location as the NavBar and logo inserted in the first page.
The rule should be not to use the copy theme option for the first page you create for a particular site. Only use the copy theme for subsequent pages being used on the same site.