I have a dateTimePicker control placed on a standard SF Maintenance Form.  The dateTimePicker control is setup to clear on null when the value is 1/1/1800.  What is happening is when I use the Maintenance forms navigator and move to a record with a null value the dateTimePicker control displays a blank field which is correct but the navigator becomes grayed out and the MaintenanceFormToolStrip only allows New, Edit or Delete to be selected.  I'm unsure of why the navigator becomes grayed out.

Using Tutorial_WinCSharp14:

I first added a dateTimePicker to the Customer Maintenance Form.  Associate the control to the cust_Created field.  I then changed the StrataFrame database in order for the cust_Created Field to allow nulls.  Then I remapped the business objects and recompiled the application.  Null out one of the records for the cust_Created fields and then run the application.  Then try to navigate on and off of that record.