Where are files stored?

Hi,

Thanks for contacting us here about this extension.

files are stored in uploads folder?

Yes, it stores in wp-content\uploads\wpfd

is there any connection with Media Folder plugin and this one?

You can import media files in Configuration by enabling Show files import (an attched image), and then you will see on the right Panel of WP File download. For more details: https://www.joomunited.com/wordpress-demo/wp-file-download/

Hope it helps!
Regards,