Is there any global setting to get File Save to show files of all types? The filtering to just the current document type wastes more time here than it saves.
If you want to see all kinds of files that are in your current folder, go to the file name box, type * (shift-8) and hit enter, all filetypes should appear.
If you want to save with a different file extention than the ones allowed type your filename and preferred extension surrounded by quotes e.g. "readme.nfo" As long as it's in quotes you won't get readme.nfo.txt