Multiple master pages - need to float specific object
I have a magazine with 3 sections. They are color specific. I created 3 master pages (one for each section). I need a design element on the master page to float above the page content. I know how to do this by making a separate layer, and this works if I only have ONE master page. But with multiple master pages, if I place the object in the new layer, it appears on ALL pages (irrespective of their Master page). How can I get a side banner object (different on each master page) to float above its respective pages?
Thanks,
Karyn