If it is a new (unsaved) document, then Ctrl+S will trigger the SaveAs
dialog too because Word is unable to simply Save as it doesn't know what
name or location to save it.
I like the F12 key, except that the keyboard drawer under my desk has the F
function keys too far back and under the desk, and I could not see them, and
the drawer cannot be extended further to the front so I could see then, so
that is why I am looking at other alternatives.
I assume that most likely there is a way that I can program the keys, but my
knowledge of Word is not deep enough for my to try that.