Any modern desktop environment, such as the UMP Desktop Mode, should include a text editor. Due to the presence of the ROX utilities for the gamma settings and file management, the ROX-edit text editor has been implemented on the UMP.
Note that the Text Editor requires a mouse and keyboard to be operated correctly (UMP-R-3XX) though the mouse is optional.
To open the Text Editor open the QuickMenu in the Desktop Mode and select it from the Editors menu. The Text Editor is not listed in the Commands Menu of the OSD.
The main purpose of the Text Editor is the manual editing of configuration files, though you can use it for any kind of task. You can save files in your home directory (the default directory that is opened when you launch the File Manager) or the public directories (/mnt/data/).
For more information on using the Text Editor see the built-in Help function and the documentation at http://roscidus.com/desktop/about_rox.