When adding a new row in a visual I experienced a weird behaviour as well. Say I add a row and I add values to all required fields. If I after typing values to the last field don't hit enter or tab and instead click save row/save information, I got an error saying the last field is required and is  currently empty. So I click the field again and tab out to mark it as completed. If I then click save information again it says that another field is empty and needs sinceit is required I need to add information. So in order to save the row I have to edit information again in all required fields. So it is like the old information is visible but the visual is not trying to pass it down to the database when I click save.