I am using the Artio ZOO extension and duplicate URLs are being generated that result in a 404 error. I have attached a zip archive containing screenshots of my settings.

I have built several ZOO applications that drive my website. Blog, Business Directory, Product Catalog, etc... I have configured the Main Menu to link to the frontpage view of my Blog app for example.

This creates a Real Url of: index.php?option=com_zoo&layout=frontpage&view=frontpage&Itemid=111

And the SEF URL is: blog

This works fine for a couple of days until a duplicate URL is generated, throwing a 404 error. See below.

SEF URL:
blog

Real URL:
index.php?option=com_zoo&Itemid=111

I have URL source tracking enabled and these erroneous URLs seem to be originating from search engine bots. See below.

Referer:
User agent: Mozilla/5.0 (compatible; Googlebot/2.1; +www.google.com/bot.html)

#1: call_user_func_array(Array, Array), /libraries/joomla/application/router.php line 435
#2: JRouter->_processBuildRules(JUri), /libraries/cms/router/site.php line 550
#3: JRouterSite->_processBuildRules(JUri), /libraries/joomla/application/router.php line 204
#4: JRouter->build('index.php?Itemid=111&option=com_zoo'), /libraries/cms/router/site.php line 97
#5: JRouterSite->build('index.php?Itemid=111&option=com_zoo'), /libraries/joomla/application/route.php line 63

Additional info:

I am including the application name in the URL to maintain functionality of things like the RSS feeds and alpha-index across my various applications.

Most of the articles in my Blog app are not categorized to achieve the desired URL structure ie: www.domain.com/blog/article-title

I tried an alternate configuration in which I included the category title instead of the app title, and nested all of the articles in a category titled "blog".

Is it mandatory for ZOO items to be placed in categories?