Without knowing what error Adobe gives you, it is hard to say.  If you can provide a screenshot of the error then I may be able to answer better.

Or you can just install manually to. Basically, you just download a zip file, unzip it, and move the folder into the Photoshop plugins folder through Finder on Mac. Then restart Photoshop and the plugins will be there.

Here is a link to the manual installers.

Manual Plugin Installation