WARNING: I am still actively tweaking upon goctave's interface, so this portion of the manual is virtually sure to be incomplete.
This file covers the user interface for G-Octave. To learn about the regular Octave interface, go here.
The bottom of the G-Octave screen contains a row of buttons called the macro bar. Each of these contains a user-defined string. Click on a button, and that string gets inserted into Octave as if you had typed it yourself. Pretty neat, eh?
To edit your personal macros, go into preferences.
The Matrix Workbench is envisioned as a quick and easy alternative to entering matrices by hand. Simply choose the size of your matrix, then enter it into the cells of the spreadsheet. Alternately, use the three fill buttons to fill it with ones, zeros, or random numbers.
When you're ready, click on one of the insert buttons to put either the original matrix, or its reduced row echelon form back into Octave.

You can use the file menu either to import or export your matrix in any of a few different formats. Usually, it will examine the extension of the file you give it and "do the right thing". At present, it supports DIF and CSV files. If it fails to recognize the extension, it will ask.