after selecting a manufacturer and going to that page, the first item in the selection pulldown list changes from the original "Select" to a "Reset".
Reset produces an url without an id eg:
which ostensibly goes to the index page.
However the formatting of this page is broken as
1) $this_is_home_page is not set, so breadcrumbs are on, and any other custom hacks using this variable break.
2) if page-specific css is in use (index_home.css), this is not applied.
ps The same thing happens if an id is missing off a cPath url, but I guess that should never happen.