So create a local table in your front-end (lets say tblSettings) with a field called CodeLength. In the AfterUpdate event of the myRadioButton control add
Code:
CurrentDb.Execute "UPDATE tblSettings SET CodeLength=" & me.myRadioButton ,dbFailOnError
Then in your form load event add:
Code:
Me.myRadioButton =dlookup("[CodeLength]","[tblSettings]")
Also, note that I would move the code that sets the combo's rowsource property from the click event of the radio button to the Enter event of the combo itself.
Cheers,
Vlad