YAMT (Yet Another Me Too). I'm on 10.8.5 (Mac) using PS CC 2014, and _have updated the Extension manager to see PS CC 2014_. I've used it to install extensions, apparently successfully. Some show up in the "about plugins"; some show up under filters (For all I know, that may be correct behavior) but in NO CASE does Extensions become enabled under the windows menu, and of course I don't have access to the pallette.
The same extensions work fine in PS CC and PS C6.
Sorry, but I cannot use Photoshop CC 2014 in this state; my extensions are vital to my workflow. I'll give 2014 a try when they fix it.