I'm trying to try out Twixtor with FCE 4.0.1 on OSX 10.9.3. I downloaded and ran the demo installer, but it doesn't show up in the Final Cut Express filters.
The installer put the fxplug into /Library/Plug-Ins/FxPlug/Twixtor/Express4.fxplug, but when I restart FCE, it doesn't appear on the Video Filters menu, or any of the other filter menus. I found some information on the web that hints this might be a folder for FCE plugins: /Library/Application Support/Final Cut Express Support/Plugins, but when I copied the fxplug into there, it still didn't help. Also, there seems to be a Plug-ins folder inside the app bundle, but when I "show package contents" and put it in there, it still didn't help.
Any ideas on how to get Twixtor into FCE 4.0.1 on OSX 10.9.3?