oxo: /var/run/$uid should be owned by the respective user, "1222 instead of 0" means you are running something as root (???), which is wrong. The second error indicates that there is no X server or that DISPLAY is not specified, which again is most probably result of you running something as root.
westford: on F21 this is correct: we want kf5-kactivities only on F22, because otherwise it breaks KDE4 applications. There is a special version of kf5-kactivities available in the plasma-5 Copr for Fedora 21 to be installed with Plasma 5.