CalendarSet version 6 documentation

property constant	can read	can write	persi stent	type	default	min	max	usage
CS_Area_Kind	√			text				Object kind = “Event” (iCal) or “ExpandedEvent” (view)
CS_Event_AllDay	√	√	√	bool
CS_Event_ClearStyle		√		ignored
CS_Event_Description	√	√	√	text
CS_Event_Duration	√	√	√	int				In seconds
CS_Event_EndDate	√	√	√	date or int	Using int variant of getter/setter, the value is assumed to be POSIX time, including the start/end time
CS_Event_EndDateAdj	√	√	√	text	Similar to the property above without “Adj”, but use timezone info: If iCal/eventUID is used, default calendar timezone is used (CS_iCal_DefaultTimezone) If area/eventKey is used, area’s timezone is used (CS_Area_Timezone)
CS_Event_EndTime	√	√	√	int
CS_Event_EndTimeAdj	√	√	√	text	Similar to the property above without “Adj”, but use timezone info
CS_Event_iCal	√			int				Owning Calendar
CS_Event_Icon	√	√		text				Comma separated icon IDs
CS_Event_Index	√	√		int				Index into the event/banner arrays when using CalendarSet compatibility API
CS_Event_InfoText	√	√	√	text				Not persistent in VEVENT, only in XML This text can be displayed in day/week view, see CS_Area_ShowInfoText
CS_Event_IsRecurring	√		√	bool
CS_Event_Location	√	√	√	text
CS_Event_Locked	√	√		int	0	0	2	0 = unlocked 1 = selectable 2 = fully locked
CS_Event_RecurrCount	√	√	√	int		0		0 = not counted
CS_Event_Recurrence	√			int				Recurrence instance (sequentially numbered) event in view only
CS_Event_RecurrEnd	√	√	√	int		0		Use POSIX datetime
CS_Event_RecurrFrequency	√	√	√	int		1	7	1 = secondly 2 = minutely 3 = hourly 4 = daily 5= weekly 6 = monthly 7 = yearly First rule in the set only
CS_Event_RecurrInterval	√	√	√	int		1
CS_Event_RecurrKind	√			int				0 = none 1 = simple 2 = advanced 3 = complex Determined by the rules used
CS_Event_StartDate	√	√	√	date or int	Using int variant of getter/setter, the value is assumed to be POSIX time, including the start/end time
CS_Event_StartDateAdj	√	√	√	text	Similar to the property above without “Adj”, but use timezone info: If iCal/eventUID is used, default calendar timezone is used (CS_iCal_DefaultTimezone) If area/eventKey is used, area’s timezone is used (CS_Area_Timezone)
CS_Event_StartTime	√	√	√	int
CS_Event_StartTimeAdj	√	√	√	text	Similar to the property above without “Adj”, but use timezone info
CS_Event_Status	√	√	√	int	0	0	3	0 = none 1 = confirmed 2 = tentative 3 = cancelled
CS_Event_Summary	√	√	√	text
CS_Event_Title	√			text				Event in view only
CS_Event_ToolTip	√	√		text
CS_Event_UID	√		√	text				Unique ID See below for additional explanations
CS_Event_UseDuration	√		√	bool				Use duration, not end date/time
CS_Event_UUID	√	√	√	text				This is the real event ID stored in VEVENT Usage is meant for iCal integration: UUID is the unique event identifier

The CS_Event_UID name can be misleading, it could be e.g. CS_Event_Key
It is actually the event key to internal map entry (key → displayed event in a view → event in a calendar)
CS_Event_UUID is the real UID of the event from “UID”. CS_Event_UID is constructed from the UID and RID, internally named MapKey and is used directly with iCalRef. “normal” event uses “u:” + CS_Event_UUID
“recurrence instance” uses “r:” + CS_Event_UUID + RID
When an instance is created in a view, “View:” + sequential_instance_number + “:” + CS_Event_UID (where the sequential_instance_number is zero when it is not a repeating event) is used to identify that event in the view.
CS_Event_UID (well, mostly the “View:” variant) is used for communication between 4D and CalendarSet.
When you click an event (CS_Area_ClickedEventID), you get this, not CS_Event_UUID.
Example: repeating event (created in Calendar.app)

BEGIN:VEVENT
TRANSP:OPAQUE
DTEND;TZID=Europe/Bratislava:20200613T100000
X-APPLE-TRAVEL-ADVISORY-BEHAVIOR:AUTOMATIC
UID:A7AA7EA3-532C-4F76-BDBC-CD0F706110C1
DTSTAMP:20200614T095222Z
SEQUENCE:0
SUMMARY:Repeating Event
LAST-MODIFIED:20200614T095314Z
DTSTART;TZID=Europe/Bratislava:20200613T090000
CREATED:20200614T095114Z
RRULE:FREQ=WEEKLY;INTERVAL=1;COUNT=5
END:VEVENT

Now you change one instance (move event from 20.6. to 21.6.) - the modified recurrence instance is added:

BEGIN:VEVENT
TRANSP:OPAQUE
DTEND;TZID=Europe/Bratislava:20200613T100000
X-APPLE-TRAVEL-ADVISORY-BEHAVIOR:AUTOMATIC
UID:A7AA7EA3-532C-4F76-BDBC-CD0F706110C1
DTSTAMP:20200614T095222Z
SEQUENCE:0
SUMMARY:Repeating Event
LAST-MODIFIED:20200614T095314Z
DTSTART;TZID=Europe/Bratislava:20200613T090000
CREATED:20200614T095114Z
RRULE:FREQ=WEEKLY;INTERVAL=1;COUNT=5
END:VEVENT

BEGIN:VEVENT
CREATED:20200614T095114Z
UID:A7AA7EA3-532C-4F76-BDBC-CD0F706110C1
DTEND;TZID=Europe/Bratislava:20200621T100000
TRANSP:OPAQUE
X-APPLE-TRAVEL-ADVISORY-BEHAVIOR:AUTOMATIC
SUMMARY:Repeating Event
LAST-MODIFIED:20200614T095259Z
DTSTAMP:20200614T095222Z
DTSTART;TZID=Europe/Bratislava:20200621T090000
SEQUENCE:0
RECURRENCE-ID;TZID=Europe/Bratislava:20200620T090000
END:VEVENT

CS_Event_VCAL	√			text			iCal event format w/o “BEGIN:VCALENDAR”
CS_Event_VEVT	√			text			iCal event format
CS_Event_WeekStart	√	√	√	int	0	6	0 = Sunday, 1 = Monday, …, 6 = Saturday
CS_Event_XML	√			text