I found the previous version of Photoshop. After clearing everything out - or so I thought - installed PS CC, followed by LR 5.5. Success! LR opened pics of all types in a normal manner. Only weird thing was, despite my renaming the old PS directory, PS CC still found my previous workspace files.
Then I installed PS 2014 without removing or altering anything... and I'm right back to where I was before: same minute+ delay in LR, followed by the same "This file could not be edited..." message even though PS 2014 does open but does nothing, same inability to open NEF or JPGs, same eventual conversion of file to a PSD dumped into PS 2014. Of course, I don't have the option of using CC now, as 2014 has taken over.
So Now what do I do? Uninstall 2014? Clear everything off again and start all over again? Obviously I missed some parts of PS/LR in my last attempt to remove everything. How do I do that.
Frustrated and frustrateder...
Ed