I'm sure others have done this already but I figured I'd post something to make it faster for anyone who hasn't already configured their OSX machine to run OneClick.
If you get the error that the JCEUnlimited Strength files are missing and you're running the proper version of Java you can copy the local_policy.jar file from your Spectrum OneClick console into the following directory on your Mac:
/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/lib/security
Note: You'll most likely need super-user privileges in order to copy the updated local_policy.jar file into place. Be sure to back up the original to something like local_policy.jar.orig before copying the new one into place.