Thanks for replying. I ran a test in ABC on a single item and the Delete/Change listing and log only show which items were renumbered and the System activity log only shows that the Delete/Change utility was used. I am pretty sure the old delete/renumber/merge utility showed which files were modified and at one time allowed you to check the ones you wanted it to modify.
I did as Brett suggested and it appears there are 29 files that were touched at that time. FWIW, the list is attached. I was concerned that based on the options that ABC company used, some files might not show, but the list seems to be complete.
If the program has to open, modify and close each of those files in sequence for every item, no wonder the process is slow.