CalendarSet version 5 includes the original API (no change needed in your existing code) and adds many new features:

• Compatibility with 32-bit and 64-bit modes (4D v15, v16 and above)
• Views: “old” month view (as in previous versions), iCal type views (day, week, month)
• Support of the iCalendar (RFC 2445) format, including importing/exporting from/to .ics files
• Predefined Styles
• Properties to fine-tune all parts of the calendars, event handling, etc.
• New commands to set and get properties
• New "Agenda" API (compatible with old 4D Agenda plugin calls)