I just found out that the Question type "Date" is not able to read and show the date value from a core field.
Here's the scenario:
1) I have a registration form with a field where I ask for the Birth date of the user. The field is linked to a core field
2) The value is correctly saved to the core field as supposed to
3) I have another DR form which should show the newly registered data. Well, it does show except for the Question type "Date" which should show the Birth Date. It is empty. If I choose a regular text box, it is correctly shown.
4) If I save a new value and open the form, it is correctly saved to the core field and shown on the form. This correct behaviour has something to do with the DynamicRegistration_QuestionResponse -table where the value is saved. But the form should show the value in the first place.
I've tried different core field types, locale versions etc., but I can't the get it to show the value.
Maybe a bug?