This is just a heads up.  I did a quick and dirty fix to an error that occurs while sync'ing duration_hours without an hour set in Sugar (i'd set a call for 30 minutes, hours was empty, not zero).  The app errored because duration_hours was an empty string or null.  It was an easy fix in Appointment.cs.  

This didn't have to be done for minutes sense you can't delete minutes

case "duration_hours" : nDurationHours = Convert.ToInt32(string.IsNullOrEmpty(sValue) ? "0" : sValue); break;