Missing menu options in 2.1.0

I was going to use the “Vocal Reduction and Isolation” effect, but it just isn’t present in the Effect menu at all. So I downloaded kn0ck0ut as a replacement and went to install it, but found I don’t have the “Add/Remove Plugins” option either. Are these options too new to be present in 2.1.0? If so, how can I achieve the same effect? If not, what could be wrong?

“Vocal Reduction and Isolation” is on the menu on the latest version 2.1.2. … http://www.audacityteam.org/