Can someone explain the purpose of the RealTime / ItemRealStartTime / ItemRealEndTime properties? How are the times different to the plain ItemStartTime / ItemEndTime properties?

ItemStartTime/ItemEndTime is expressed in units defined by the time of the timeslots.

ItemRealStartTime/ItemRealEndTime keeps the full precision of the time (in the case the timeslot time unit is less precise than the events real start/end time)

I kept coming back to the ItemReal properties but could not get them to work, then I found the undocumented PlannerItem RealTime property. This is false by default but setting it to true allows the ItemRealStartTime and ItemRealEndTime to work as I would expect. 

Life would have been a lot easier if this property was mentioned in the manual! 

Thanks for your feedback.
We've taken a note to take this in account when working on a manual update.