Hi סאלא,
Are you using the trial version of V-Justify, or the full version?
The trial version turn the text into gibberish (“adding extra letters” as you put it) – this lets you check out V-Justify and see if it suits your needs, while limiting it’s real-world usefulness.
The full, paid-for version removes this limitation, of course.
If you are using the full version, you should not be seeing any extra letters appear, so let me know if it’s still happening.
Thanks,
Ariel