Modify Data -> New -> file type

Is it possible to add a file type to the list of those available in the default submenu (Data -> New)? I am looking for a way to quickly add an OmniOutliner file to a group. Suggestions?

You can add all your own template files by selecting Data > New from Template > Open Templates Folder and putting the file(s) there.

That is very straightforward. Thanks!

No problem.