You can redefine the Ctrl and Alt cursor keys into line drawing characters by executing a macro file as follows from the qed command line:
x /usr/lib/box.macros
Experiment by typing each Ctrl–cursor-key and Alt–cursor-key within the editor. The Home, PgUp, PgDn, End and 5 key should also be used. Some of the keys will move you in the most natural direction for drawing a box, however, the Ctrl–↓ will not move beyond the last line of your file buffer. You can press carriage return to open up room.