** I would also like to have a secure version of the same calendar for the admin to add events. **
What exactly do you mean by "secure"?
If you mean password protection on the server side like via an .htaccess file, you'll likely have to install 2 separate CalendarScript installations, each in a different directory.
You can of course set different permissions from within CalendarScript for each of the individual calendars a single installation has access to.
Dan O.
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