Hi,
I am now maintaining the medialist plugin, updated release 2015-06-25.
For clarification, the plugin does not assume using in the sidebar.
At least recent version, you may find following HTML comment (PlaceHolder) in the HTML page source.
<!-- MEDIALIST:@NS@: -->
If you visit the sidebar page, the medialist contents shown in the main page, however not shown in the sidebar area.
I could not find the way how to replace the PlaceHolder in the sidebar area. I guess likely need javascript or AJAX solution.
Any suggestion and push request are welcome.