At the command line or in a graphical text editor.. yes you would need to modify that file.
Theres additional info on customizing the GUI
HERE and it touches on that same topic but still doesn't go into great dertail
Also a video is available..
Installing app and Icon on Desktop of AA1
and
add your own desktop icons
That should get you rolling again I think..
more AA1 links in my sig,
enjoy !