For item 1, I would have a date field and keep the date in it in the proper format, then I would have a text field that you take from the date field like this:
Dim sDate As String
Dim dtDate As Date
dtDate = Me.DateField
sDate = DatePart("yyyy", dtDate) & DatePart("mm", dtDate) & DatePart("d", dtDate)
Me.StringDateField = sDate
For the second item, store the string date, and then add another column that is a number value, and just take the Max of the number culumn where Date = sDate and add 1.
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