Don't do this, you're supposed to launch Mono from a command line, passing a name of Launcher as a parameter.
Use these guides:
Automatic install: Technical Issue - Noob Probs on Mac: App Support JKJA folder is gone
Manual install: [SOLVED] - STRUGGLING with Mac installation.
Please stop retelling error messages with your own words.
You absolutely, positively must quote all error messages you got fully and entirely, with omitting a damn word.
Screenshots are also welcomed.
I was able to fix the problem. I just went through the ModDB site, found the 1.5.1 full version, slapped it in the contents of the Jedi Academy folder and it was fine.