The issues reported here by David Haslam were detected by a detailed comparison with the text extracted from the independently created KJV1769 e-Sword module provided by Art Dunham, as once hosted on the Spanish Reina-Valera-Gomez website and downloaded before that site was redesigned. That e-Sword module was not completely without minor errors, but the comparison proved fruitful in identifying some minor issues with both works.
Text and markup issues
Translators' added words currently not displayed as italics
Due to the use of alternative transChange markup
I found 17 instances where <seg subType="x-added" type="x-transChange">...</seg> was used to mark added words. The SWORD engine does not assign italics for words marked like this. The added words are listed below.
Judges 11:3 of Micah 7:12 from Matthew 18:28 him Matthew 21:28 certain Matthew 21:31 his Matthew 22:6 them Matthew 23:4 themselves Matthew 25:37 thee Matthew 25:38 thee Matthew 26:17 feast of Matthew 26:45 your Matthew 26:67 him Mark 5:29 her Mark 10:4 her Luke 9:36 it Luke 11:19 them John 5:36 that
Translators' added words that incorrectly include a punctuation mark
I found 20 instances where the transChange markers for an added word also included the punctuation mark at the end of the sentence. Admittedly, displaying a full-stop or a comma in italics is of minor cosmetic significance, yet nonetheless this is structurally incorrect. For convenience here below I have used square brackets to abbreviate where the transChange markers are.
Matthew 11:27 [him.] Matthew 13:17 [them.] Matthew 19:12 [it.] Matthew 22:46 [questions.] Mark 11:14 [it.] Mark 12:34 [any question.] Luke 10:22 [him.] Luke 10:24 [them.] Luke 11:44 [of them.] John 1:18 [him.] John 4:26 [he.] John 14:14 [it.] John 19:27 [home.] Acts 7:53 [it.] Acts 16:13 [thither.] Romans 13:14 [thereof.] I Corinthians 10:13 [it.] II Corinthians 7:16 [things.] I Thessalonians 5:24 [it.] Revelation of John 2:17 [it.]
Minor typographical errors
- In Exodus 32:32, there are two hyphens after the word sin. In printed editions there is a horizontal line (or an mdash?).
- Some possibilities: horizontal bar: ― or emdash: —. There are also some 2- and 3-em dashes in the Unicode pipeline.
- In Romans 4:18, the word nations is followed by a semicolon. In printed editions there is a comma.
- In the colophon after Philemon 1:25 there is a comma after the word Onesmus which is not present in printed editions of the KJV.
- In Acts 3:7 the KJV module has the spelling ancle. The comparison text has the spelling ankle. Both spellings are found in different printed editions of the KJV. 
- This is a strange inconsistency. In the KJV module, the spelling ankle occurs in 4 other places in the OT.