HI again, Gil.
There isn't a hard and fast rule about when to use vertical and when to use horizontal figured-bass formats. All I could tell you what I would have done in that case. If a particular agency wants a different answer, that is their privilege. I apologize if I have caused you any trouble. All you should have to do to attach a file is click on the "attach files" button below where you are writing your message.
Best to you,