You can export the calendar that you have in Wealthbox to your iMac Apple Calendar in a read-only format.
To do so, go into your Wealthbox account > Applications > iCal > "Settings". Here you will find a link that you may copy and paste into your iMac / Apple Calendar. Click here to find your calendar web address.
In iMac Calendar:
Select “New Calendar Subscription"
Paste the link you copied from Wealthbox in the Calendar URL box
Choose the calendar name and color
Set the Auto-refresh to "Every 5 minutes"
Make any other adjustments you'd like to the settings, then click "OK"