Hello.
Unfortunately, Booking Calendar does not support importing/exporting to ical/ics, yet.
Sorry. This features exist in out TODO list for future updates and have high priority.
But currently I can not say about the exact day of implementation. Hope its will be available ASAP.
Actual versions of Booking Calendar support import of events from Google Calendar to Booking Calendar. Also manual export of booking (by clicking on link) to Google Calendar, will be available with next update which will come during close time (week or 2).
Paid versions of plugin support of export bookings to the CSV files (which possible to open in MS Excel or some similar applications).
Kind Regards.
