If you satisfied with CC 2014 and don't use any of the features and support Adobe has removed your plug-ins still work and your are effected by the new bugs. There is no need to keep old versions installed. I keep old versions installed as a safety net.
Thank you very much for replying. I have another concern. So I have 2
Photoshop versions installed now - PS CC and PS CC 2014.
In PS CC, I have installed Nik Collection. It works fine.
In PS CC 2014, I installed Nik Collection as well, using the Nik .exe file
and the installation wizard. Upon opening PS CC 2014 and clicking
"FILTER", Nik Collection can be seen and is not grayed out. In fact, if
clicked, for examole, the Color Efex Pro, it opens to the main Color Efex
Pro Window. HOWEVER, after choosing an effect within Color Efex Pro, and
clicking "OK", Photoshop cc 2014 does not apply the effect. Is this
because The Nik Collection is installed in 2 PS versions? I have no issues
with respect to my ALien Skin Plug-ins which are installed in BOTH by PS CC
and PS CC 2014. I have emailed Nik Collection and they have not yet