When doing "Save As" in applications, the most normal next action is
to type the name of the filename that you are trying to Save As.
However, the cursor seems to be set at the file filter field - one
that is not used very frequently.

I continually find myself half way through typing the new filename
before I realise I am not really entering data in the correct field.

So my wish is that in the file Save As dialog box that the intial
cursor position is in the filename field.

My apologies, but I am slightly out on what happens.

The problem only arises when I have selected a new directory with the
mouse from the bar across the top. In this instance the filename where
you will type in the new name appears to be selected (except for the
extension) and therefore there is a hidden expectation that typing will
replace that selection. In fact it doesn't, as I said, its filtering or
selecting from the filelist below.