[UbuntuGnome] Lenovo Thinkpad X1 Carbon 3rd Gen

I'm using a Lenovo X1 Carbon 3rd Gen ruing ubuntu. A couple of days ago I upgraded to Ubuntu 16.04 ruing Gnome as my desktop.
I normally disable the trackpad (why do they bother with that - it essentially makes the computer unusable) in the bios. At first everything worked fine but after I did a subsequent
"sudo apt-get dist-upgrade" the trackpad started working - though still disabled in the bios. There seems to be no way to disable it, either in the bios or in the gnome extension that supposedly handles mouse and touchpad config.

The only way I have found to tu it off is to modify /usr/share/X11/xorg.conf.d/50-synaptics.conf by replacing the line MatchIsTouchpad "on" to "MatchIsTouchpad "off" in Section "inputClass".
Unfortunately this also tued off the trackpoint and the computer is unusable.

Is there a way to modify the config file to allow trackpoint to work without touchpad. Sorry if this is the wrong topic but not sure whether this is a hardware or a software issue.

Thanks.