The latest CKEditor plugin incorporates all supported languages offered by CKEditor, so adding a language file probably wouldn't help. However, if your store is set up to use a language that's not supported by CKEditor then CKEditor won't work for you unless you build your own language pack for it (by cloning the appropriate language .js file and translating its contents).
So if language isn't the issue, then you've probably got jQuery or javascript conflicts on your site's admin files, or you've got addons installed that have changed the HTML normally in the latest version of Zen Cart's admin pages which denote the hooks for the editor to load.
That is of course assuming that when you said you "copied the files 9 times" that you were copying them to the correct locations as explained in the readme, including the files that belong in your (renamed) admin folder.
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