[i]I have no live buttons on a sub-menu screen.[/i]
I suspect there are a few ways around this. One way I’ve done this is to click/select a link from another menu/screen and press Ctrl+C (copy) then returned to the screen without a button, clicked on the screen to select it, and pressed Ctrl+V (paste).
Then go to the properties of the newly pasted link to make the relevant changes.