You need to edit file in ~/.fluxbox/menu
The systax is very simple..
Just add this line in the correct submenu
[exec] (Name) {/path/application}
Also do this
ln -s /full_path_to_executable /usr/bin
as root
Add to ~/.fluxbox/menu
[exec] (firefox) {/home/opti/Apps/Firefox/firefox-installer/firefox}
Then run this as root
ln -s /home/opti/Apps/Firefox/firefox-installer/firefox /usr/bin
– Main.FredPettis - 2010-10-13