I attempted this method, and can definitely say it does not work. There is no + icon that appears once you are inside the box. Also, even if you try to override the $0 amount with the actual amount, the system overrides your override and puts it back to 0. So after testing this, I can say, it's not a bug in a traditional sense because this was done by design, however it is a bug in the sense it doesn't work well with the software these other companies are using when you do the import.
