Ok. I already had Text File in New menu. Here's what I did to get a template file.
I added a new string named FileName and for value Template.txt
In the folder C:\Windows\ShellNew I made a file named Template.txt. The contents is:
This is a text file template.
Now if I right click the desktop or in a folder, select New text document, name it, then double click, it has the text from the template.
One thing I notice I can't do it directly under C:\
It has to be in a folder. The permissions situation with W8 seems even worse than W7 now. Every move is hamstrung. I can't even save a file from Editpad directly into C:\Windows\ShellNew. I have to save it somewhere else, then drag it. Really asinine.
Anyway, I hope the template text default was what you were interested in. If not then, Never Mind.