monpelaud

he only way to change the root directory is to modify the source code.
In lines 84 and 86 replace WP_CONTENT_DIR by the path of the root directory you need.
For example change:

function upload_widget_full_path( $instance ) {
		if ($instance['upload_path']) {
			$full_upload_path = WP_CONTENT_DIR.'/'.$instance['upload_path'].'/'; }
		else {
			$full_upload_path = WP_CONTENT_DIR.'/';
		}
		return $full_upload_path;
	}

by

function upload_widget_full_path( $instance ) {
		if ($instance['upload_path']) {
			$full_upload_path = '/yourrootdir/'.$instance['upload_path'].'/'; }
		else {
			$full_upload_path = '/yourrootdir/';
		}
		return $full_upload_path;
	}

‘yourrootdir’ is the common path for all instances of the plugin.
The other part of the upload path of each instance ($instance[‘upload_path’]) can be adjusted through the parameter “Upload Path:” of the plugin.