Scrivener in 1894 used the Beza text and modified it to more closely match what must have been the underlying Greek text used by the KJV translators. Note that the Stephanus text of 1550 was the basis for the Beza text of 1598 that was the text used for the KJV. In addition to NA27/UBS4, there are quite a few other Greek NT texts available.The BNM/T version is based on the NA27 punctuation and the GNM/T on the UBS4, so one can detect those differences. Since BW7 does not provide paragraph formatting, one of the main differences between and NA27 and UBS4 is obscured.
(Sections 44a and 44b of the BibleWorks7 Help file provide excellent coding scheme tables and explanations of the BW7 and Friberg coding philosophies.) For the NA27/UBS4 texts, there are schemes by Gramcord, Logos, Friberg, Swanson, and a custom one by BibleWorks. Each coding scheme is slightly different, and so one has to be somewhat familiar with the design of each. Morphological coding is independent of NA27 or UBS4, so Rick doesn't mention it, but it is a significant factor in one's use of the texts.With his post as an impetus, I pulled together a quick spreadsheet showing how NA27 and UBS4 are implemented in Accordance, BibleWorks, and Logos. As he points out, the Greek texts are essentially the same, but there are differences in punctuation, casing, spelling, and formatting. Rick Brannan from Logos recently posted a very helpful article on the differences between the Nestle-Aland27 ( NA27) and the United Bible Society 4th Ed.