All that HTML5 supports: .MP4, .WEBM, .OGG and .OGV. To subtitles, just .SRT files for while.

Change the subtitles encoding to the correct one. Just click on 'settings' (engine icon) button. Default is ISO 8859-1.

Change the minimum file size on 'settings'. Default is 100MB.

Check if the extension have permission to access local files (step 2). Check if are valid movies in your folder. Check if you are using the lastest Chrome version.

The extension was tested on Windows 7, Windows 8.1, Ubuntu 13.10 and Mac OS X 10.9.1 running the Chrome (32.0.1700.107 or greater).

Me.

eu@lucasfranco.com.br.