TARDIS
I also had errors like that trying this method.
When following the steps on the neutronscott wiki, using vi to edit the copied file (I used only the one, not both, as I didn't need it) it should let you save. I've never been great with vi, but it did let me save as it's outside the system path. Only changed "messenger" to say FOCUS.
You'll also need the props file. With different details. I copied the one from the mouse zip, edited it, and pasted my details in the newly created one.
Once saved, I rebooted and it was a new module that worked after a reboot. You will have to change the key in voice access settings to it, and it shows up as "focus" when pressed.
Maybe I'll try to write up a little more detailed set of steps when I have some time. The wiki had all the commands detailed but maybe presenting it a little differently could help.
Agree about this forum!