The screenshot was from Nginx web server running on v4 firmware, look for my webhosting mods thread [APP] WebHosting for firmware V4+ (10/2015) if you want Nginx, MySQL and other CGI stuffs.
I haven’t tested but if you want to try on the existing Apache2 web server (from what I see it should work), as per-norm warranty void disclaimer applies, extract the zip into /var/www/htdocs/ftp then access it from http://wdmycloud/ftp or http://192.168.1.x/ftp or even your DDNS or public IP (provided you did the port forward).
