Going through the Tutorial.  Adding records to Contacts Form. 

Intentionally added bad date (US): 13/01/2004.  Record gave no warning that it was bad, made auto change to 01/13/2004. 

Added bad date 13/25/2004, record was saved, date field is empty, no warning.  More bad dates are rejected with no warning, just leave a blank date field. 

See same issue with Call Details, Time of Call field.  If bad value, record is saved with blank value, no warning.

I think that there should be a warning if the format is not a valid date.  This type of error should not require programming to validate.  It should not make a change by itself, and it should not make a blank.  Many typists never look at the screen, and they will not see that the date/time field has been cleared/changed.  Best option would be send alarm when doing exit on field vs. when closing record, since other programming might be a function of this value.