Several region templates have double dashes in their names. Camino and several other browsers seem to mis-interpret that as an end comment and cause serious layout damage.
I suggest changing all comments like this:
</section><!-- region--sidebar.tpl -->
to just a single dash like this:
</section><!-- region-sidebar.tpl -->
The user should still understand what section is ending and no breakage occurs in some (lesser used) browsers.