Have my original Jimmy Buffett Don't Stop The Carnival. Have purchased 4 of these (hard to find) and given 3 to friends as gifts. Now I want to duplicate my CD and archive the original. However the disk contains *.nba files...such as bckbrowse.nba, cdplay.nba, etc. The disk also contains some .dll files which are of the video. What are .nba files and how can I copy this disk?