I've got the original Start, Finish, and Duration filled with dates and times. Trying to track the progress of a project by entering dates and values into Actual Start, Actual Finish, and Actual Duration changes the original values along with 'Actual'; I'm having to change the original values to reflect actual times, which makes comparison meaningless. This happens with 'Actual Work' and 'Percent Complete' as well-- I'm unable to have a task complete before its original end date. Help!