I've used the plugin to convert a few posts to pages and the pages show up in the navigation hierarchy of my website but they have disappeared from both the posts and pages section of the dashboard.
Here are a few details about the site:
-I'm using the "Modest" theme from Elegant Themes
-The affected pages are at the 4th level hierarchy (but do not reappear after changing them to any level of hierarchy)
-I have installed the following plugins: List Category Posts, Post Type Switcher, Social Login for WordPress, Spam Free WordPress, WPML, Q2W3 Post Order (disabled), WP Post Sorting (disabled)