I had the same problem.
When I import the fx or save the fx from the downloads page I get a bunch of .zip files which when extracted do not contain the needed .eff files (the .eff files are what open in the editor). I believe the .zip is actually the .eff that windows has renamed and all you need to do is manually rename the extension (change the .zip to .eff).
[attachment=1:18xu7y22]ImportFix_01.jpg[/attachment:18xu7y22]
[attachment=0:18xu7y22]ImportFix_02.jpg[/attachment:18xu7y22]
[attachment=2:18xu7y22]ImportFix_03.jpg[/attachment:18xu7y22]
This worked for me.