Thank you very much Joseph for your reply.
I know the option, “Handle keys from other applications”. I've experimented with it a bit. Both checked or unchecked it doesn't solve the issue.
If I leave it unchecked, once pressed the "delete" button, no audio feedback.
If I leave it checked, once pressed the "delete" button, NVDA reads just one letter of the deleted syllable.
Anyway, I have to leave it unchecked, otherwise I encounter other problems, the main one is that typing punctuation stops the voice. While I need that punctuation doesn't stop the voice and also it isn't red. I can obtein this only if I leave that option unchecked.
I'll contact the steno application developers and ask if they can contact you.
Do you confirm "info@..." is the right email?
I don't have your contact, under your profile detail I cannot find.