aqbrown,
The route to the keys preferences, on Linux, is Window->Preferences->General->Keys. However, on a Mac, the main link to the preferences for any application in a common place, the leftmost menubar item, which is the application name. In our case, that’s “MyEclipse Enterprise Workbench”. If you click that menu, you’ll see a Preferences item in it. Just click on that and follow the rest of the route to the keys preferences.
The MyEclipse->Preferences only show MyEclipse related preferences, whereas Keys preferences are from the base eclipse.
Please let us know if this works for you.