Merge this app folder with a magento project's one.
Then, go to the system configuration and enter the CommerceConnector configuration (System > Configuration > Catalog > Catalog > Commerce Connector)
Add this line to your layout/catalog.xml:
<block type="commerceconnector/listSellers" name="commerceconnector" as="commerceconnector">
<label>product.commerceconnector</label>
</block>
Add this line to your app/design/frontend/YOU/default/template/catalog/product/view.phtml:
<?php echo $this->getChildHtml('commerceconnector') ?>