Ok i think i got a bit further.

I build most of the stuff myself. The patch was not necessary. Dependencies for the daemon are:

https://salsa.debian.org/debian/libg15.git

https://github.com/libusb/libusb-compat-0.1

sudo apt-get install libg15render-dev

When building the Daemon there is an outdated open command, you have to add the O_WRONLY argument.

Different to what the INSTALL said I did not have to adapt the installpaths, a ldconfig was sufficient. I think i got the same Problem with the daemon not starting on reboot, didnt and started it with sudo. It was a bit confusing that any --version without sudo returns not running, but the process is still alive after a sudo start.

I then was able to change the keyboard layout in

sudo dpkg-reconfigure keyboard-configuration

to the g15. But apparently it is the name for the G15Daemon and the g15macro code.

A restart succeeded.

Now the interesting parts. if you look at the binding of the G keys with xev i saw it change along of the install process. I started with F1-F12 and with the Installation of the daemon the binding changed. To the binding OP described. So i think the driver was successfully installed and can work with an G11. After setting the Keyboard layout all keys are dead, no longer recognized by xev.

I then installed g15macro from source from

https://sourceforge.net/p/g15daemon/wiki/Home/

had to add -lpthread in the Makefile. I also installed stats, but from what i could see its for writing the display so i removed it again. It behaved the same as g15macro in it started, didnt throw an segfault but simply got stuck not doing anything. Had to kill both.

Version succeeds and i can enable debug mode. That however just gives me the one line of debug started. if i use the keysonly option the program ends. Which makes sense when looking at the code. So the configure_mmediakeys and change_keymap should have run through. Thats the part that OP also successfully run through. It looks like he crashed in restore_config, i dont reach that far but seem to get stuck in the opening of the config. Maybe thats still my rights problem.

The next step is i think something that is mentioned in the Debian documentation for the Daemon. It comes with a contrib folder and an FAQ and mentions the need to change your X-Server configuration to use the keys. But they mention it as the prerequisite to change the keyboard layout. Here it might be the problem with the configuration for the G11 vs the G15, not sure.

If OP reads this i would recommend installing macro manually to do some flashlight debugging, not change the keyboardlayout yet and check the X-Server config.

Cheers!

Other sources: https://wiki.archlinux.org/index.php/Logitech_Gaming_Keyboards