just create a ItemCreating event handler in the CustomItemTemplates demo:

private void calendar_ItemCreating(object sender, ItemConfirmEventArgs e)
{
e.Confirm = e.Item.StartTime > DateTime.Now;
} 

Start the app, select a range before the current time and hit a key (which would create a new item but which gets cancelled by the event).
Now change the CurrentView with the combo (without clicking somewhere inside the Calendar first) for example to ResourceView and nothing will happen. But when trying to move items around or trying to do a new selection you'll notice that the calendar indeed is in ResourceView mode.

It also skips now adding of new resources (when in grouped mode), or won't update the day headers in TimeTableView with enabled navigation buttons.

A new version of the control can be downloaded from here:

https://mindfusion.eu/_pln_trial/MindFusion.Scheduling.Wpf.2.1f.zip

In addition to a fix of the above problem, this version also implements some of the previously requested features - Calendar.ResourceView*TimelineClick set of events for the three resource view timelines, Calendar.MonthWeekHeaderClick fix and CLS compliance come to mind.

Regards,
Meppy