I have "AllowNull" set to True On UltraCalendarCombo but once I set the value to Null and I try to move the focus to somewhere else on the form, its automatically putting the focus back on the UltraCalendarCombo and forcing me to pick a date.
I don't have this problem if I am selecting a null value from a UltraCalendarCombo that is embeded on to a UltraGrid
I was not able to reproduce the problem you describe here with a simple test; unless you specifically handle the Validating event and cancel it when the value is null/DBNull, the control does not retain the input focus. You might want to report the issue via the web support form so that you can provide the details necessary in order to reproduce this behavior.
I am not doing anything to the Validating event
I just noticed that I only have this issue when I attach the UltraCalendarCombo to a BindingSource. If I just drag and drop the UltraCalendarCombo to the same form, I don't have any problems setting the value to Null and setting the focus elsewhere on the form.
It's only when I do DataBinding to the UltraCalendarCombo it forces me to pick a date. The workaround I am doing right now is setting the "CausesValidation" to False.