you can add every other page to the index page container, but not the index page itself, of course

On every transitionIn call of every page (or in the abstract page, with some logic to avoid the index page) reference the movieclip you want (like Gaia.api.getPage('index').content.container_mc) and addChild the page (this). Not sure about it, but you might need to re-parent the page back to it's loader inside transitionOutComplete (before calling super.transitionOutComplete). Check without it if the pages unload correctly, do it if they dont.