I have a mac running OSX 10.9.4.
I have Photoshop CC 2014.1.0 / 20140730.r.148 x64
I have Extension Manager CC 22.214.171.124
According to "Creative Cloud" manager, my versions of software are up to date.
I tried installing three different extensions. None of them load. When I double click on the extension file, it launches Extension Manager CC, but it appears that Extension Manager does not recognize that I have other Adobe products installed. E.g., "Failed to install the extension 'XYZ.' Please make sure the manifest.xml of this extension is valid and the Extension Manager recognizes at least one product which the extension supports." I get variations on this message, but the common thread seems to be "Extension Manager recognizes at least one product which the extension supports."
When I choose "Manage Extensions" from the Help menu in Photoshop, it just launches "Creative Cloud" manager, which tells me all of the software is up to date. (The first time that I tried this, it re-installed Extension Manager CC). Nothing else happens -- e.g., it does not launch Extension Manager.
Any suggestions? How do I get Extension Manager CC to recognize that I have Photoshop CC installed?
One more thing -- I have seen references in postings to an "Extension Panel" under the "Window" menu. I do not see that item in Photoshop CC. (There is "Browse Extensions Online," which allows me to find more things that I can't load).