This extension will convert URL's like
http://magento170.local/furniture.html?color=36
into
http://magento170.local/furniture/brown.html
The layer filter items try to load a SEO friendly URL from the database. If it does not exists it will be created automatically.
An addtional router will take care of the rewrite magic for those special URLs. We use some rewrites here to hook ourselfs into Magento's layered navigation system. So beware of this behavior.
To make the module create stable and strong urls please add positions to your attribute configuration since those positions are used to order the speaking option values within the URLs. More important attributes are to be positioned first within the attribute configuration and thus are positioned first within the resulting URLs.