Regarding your interest in viewing the original orders,reports,letters etc..from which the Official Records were written.I had a friend in Northern Virginia that would go to the Archives and make copies for me from the original Special Orders some of which were not listed in the CSR's of the particular mentioned soldier.As Wm.Shea says,it is probable there are numerous transcription errors and some material in the Archives which is not in the ORs and perhaps the Supplement.
MWT