I just installed netrunner and am so far quite pleased with the distro. However, I was trying to install a new theme and noticed that the theme manager didn’t exist: Right click on desktop -> Desktop Settings (or Appearance Settings, depending on which version you use) -> New Theme… -> (Choose a theme) -> Install.
You’re talking about plasma-themes? What about copying the theme to '/usr/share/kde4/apps/desktopthemes" and configure it with the systemsettings(-gui) after that?
Hope that helps…
bye
sA!NT