You can set up an automatic feed of events from your CalendarWiz calendar into your Mac iCalendar.  Please note that these events will be read-only in your Mac's calendar application.

STEP 1: Enable your CalendarWiz calendar's iCal feed via:
Admin Menu > iCal and RSS > Click to enable iCal > Select categories to include in feed > Save
Note: iCal link appears at the botton of screen.  iCal button appears on calendar nav bar.
 

STEP 2: Next, go to your Mac. In Calendar, choose File > New Calendar Subscription

STEP 3: Enter or paste the CalendarWiz iCal link, then click the Subscribe.

STEP 4: Enter calendar name and color. Review refresh options and set as you wish. Optionally, select Location as "iCloud" if you wish to pull this feed into other Apple devices. Click OK.

If you choose location to be iCloud: Apple recommends that you update your iPhone, iPad, and iPod touch to the latest version of iOS, and Mac to the latest version of macOS.  Make sure you’re signed in to iCloud with the same Apple ID on all of your devices.

Note: if you need to include private categories in your iCal feed, simply follow this link.