Okay, got it working using Automator.app (an Apple built-in app)
Attached is an application generated from Automator.app that runs the perl script, no user intervention needed beyond placing JMCecils files in your prefs dir. ( ~/Library/Preferences/Cubase 7/ )
Here are the terminal commands the Automator script runs:
cd ~/Library/Preferences/Cubase\ 7/
perl ~/Library/Preferences/Cubase\ 7/genCommands.pl
sleep 2
open ~/Library/Preferences/Cubase\ 7/KeyCommands.html
edit, Apr 10, 2014: the file paths above are for Cubase 7, if you are using this with a different version be sure to edit the paths to the version you are using.
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Get Cubase 7 Key Commands.zip (1.47 MB)