I\'ve added a CMS page wich shows all the products listed under the \"All Products\" category by creating a CMS page with a \"two column with left sidebar\" layout, and in t
To display layered navigation on cms page you have to set root category to Is Anchor=Yes.
One possible reason layered navigation does not show is because you also need to configure your attributes to show in layered navigation.
Please check the below link for calling layer navigation in CMS Page
http://www.webdesign-gm.co.uk/news/web-design/magento-web-design/layered-navigation-on-home-page-or-any-cms-page-magento.php
Or you can try this Design tab->Page Layout->Layout Update XML:
<reference name="left">
<!-- Layered Navigation Block -->
<block type="catalog/layer_view" name="catalog.leftnav" template="catalog/layer/view.phtml" >
<action method="setCategoryId"><category_id>40</category_id></action>
</block>
</reference>
<reference name="content">
<block type="catalog/product_list" name="home" template="catalog/product/list.phtml">
<!-- Product List View -->
<action method="setCategoryId"><category_id>40</category_id></action>
<block type="catalog/product_list_toolbar" name="product_list_toolbar" template="catalog/product/list/toolbar.phtml">
<block type="page/html_pager" name="product_list_toolbar_pager"/>
</block>
<action method="setToolbarBlockName"><name>product_list_toolbar</name></action>
</block>
</reference>
Open CMS->Pages->[your page] in Magento Admin Panel. Add the following layout instructions to Design tab->Page Layout->Layout Update XML
<block type="catalog/product_list" name="product_list"
template="catalog/product/list.phtml">
<action method="setCategoryId"><category_id>3</category_id></action>
<block type="catalog/product_list_toolbar" name="product_list_toolbar"
template="catalog/product/list/toolbar.phtml">
<block type="page/html_pager" name="product_list_toolbar_pager"/>
</block>
<action method="addColumnCountLayoutDepend">
<layout>empty</layout>
<count>6</count>
</action>
<action method="addColumnCountLayoutDepend">
<layout>one_column</layout>
<count>5</count>
</action>
<action method="addColumnCountLayoutDepend">
<layout>two_columns_left</layout>
<count>4</count>
</action>
<action method="addColumnCountLayoutDepend">
<layout>two_columns_right</layout>
<count>4</count>
</action>
<action method="addColumnCountLayoutDepend">
<layout>three_columns</layout>
<count>3</count>
</action>
<action method="setToolbarBlockName"><name>product_list_toolbar</name></action>
</block>
<block type="catalog/layer_view" name="cms_layer" as="cms_layer" before="-">
<action method="setCategoryId"><category_id>3</category_id></action>
</block>
Also insert ID of desired category in 3 (2 times). Open desired category of your store through Catalog->Manage Categories. Make sure that Is Anchor=Yes on Display Settings tab.