Hi,
how do I add a new text file so it’s the first file underneath a folder.
When I select the folder then add a text file the text file ends up all the way at the bottom of my manuscript and then I have to drag it up to where I want it. Is there an easier way to do this?
Create it as the second file by selecting the first file, and then Ctrl-Cmd-UpArrow to switch places with the first. That’s what I do anyway. 
What I do is select the first word in the current topmost file, hit COM-K and immediately generate a new file above that one. (You’ll probably want to move that switched word back to what is now the second file.) Also handy for inserting a blank file anywhere in the folder.
ps