I am using gnome...and it worked exactly as you instructed.
I "create new file" and copy and pasted the command:
su -c "ln -s /sbin/boot-game-os /bin/boot-game-os;echo '[username] localhost = NOPASSWD: /bin/boot-game-0s'>>/etc/sudoers"
then I took out [username] and replaced it with root. Then I opened a terminal and entered the command. I hit enter, runs its course and it now tells me button exists...
...right click on desktop..."create launcher" and under command:
sudo boot-game-os also check "
run in terminal"
Works like a charm...now when I want to get back to a blue ray movie...I have a functioning icon button back to the game os. cool.