Wikistyle links in your WordPress blog.
Simply put [[ and ]] around a post title within your post or excerpt and Interlinks will turn it into a link for you. You can also use the more advanced wiki style [[Post Title|This is a link to a post]]. If a link is red then the page doesn't exist.
From the plugins page on http://www.craftycoding.com.
The settings are in your Dashboard -> Settings -> Reading page.
From the plugin page at http://www.craftycoding.com/products/wordpress-plugins/interlinks/.
Yes you can. Crafty Coding is a professional web design and development company, meaning you can hire us for just about anything including customisation of our plugins.