If you want to install ruTorrent you must install a web server, eg. Apache.
If you've already installed another web server, you must first uninstall it or
disable it. List of supported web servers:
  apache   Apache web server
  nginx    nginx web server (lightweight)
  lighttpd lighttpd web server (lightweight)
  none     Don't install a web server
Select one of: apache nginx lighttpd none
Enter name of web server [apache]
Do you want to install ruTorrent? [Yes] y

ruTorrent requires a working rtorrent built with XML-RPC support.
Do you want to build rtorrent? [Yes] y
Do you want to install the autodl-irssi ruTorrent plugin? [Yes] y

If you want to automatically start Irssi and rtorrent when the computer boots,
install the startup script.
Do you want to install the startup script? [Yes] y

===================== USER =====================
This is the user running rtorrent and/or Irssi.
Don't use the root user. Use a normal user!
Press ENTER to stop adding users.
Enter name of user: drkadzija
User drkadzija does not exist.
Do you want to create user drkadzija? [No] y
Creating user drkadzija.
Enter the user's password:
Enter new UNIX password:
Retype new UNIX password:
Sorry, passwords do not match
passwd: Authentication token manipulation error
passwd: password unchanged
Failed to set password.
Enter name of user: drkadzija

The ruTorrent user is the name you use to log in to ruTorrent.
Enter ruTorrent user: [drkadzija]
Enter your ruTorrent password: 1q2w3e4r88

===================== USER =====================
This is the user running rtorrent and/or Irssi.
Don't use the root user. Use a normal user!
Press ENTER to stop adding users.
Enter name of user:

vsftpd is a very secure FTP daemon.
Do you want to install vsftpd? [Yes] n

Webmin is a web-based administration tool for your OS.
Do you want to install Webmin? [Yes] n

You can execute this command as the root user (Ubuntu: use sudo):
  sh autodl-setup -p -a -u drkadzija::drkadzija:1q2w3e4r88 -w -s --apache --rtorrent --rutorrent

Use the autodl-irssi ruTorrent plugin: y
Re-install the autodl-irssi ruTorrent plugin: n
Install autodl-irssi: y
Users:  drkadzija::drkadzija:1q2w3e4r88
ruTorrent is password protected: y
ruTorrent base path:
Install startup script: y
Install web server: apache
Build rtorrent: y
Patch rtorrent: n
Install ruTorrent: y
Install vsftpd: n
FTP port:
Use FTPES: n
Install Webmin: n

Press Ctrl+C to cancel or ENTER to install.