Hm, according to this in a thread that covers the same screen as yours nothing more should need to be adjusted than “/boot/userconfig.txt”.
BTW did you add the line break in “/boot/userconfig.txt” I mentioned above and reboot? If not, try that first. If touch still should not work maybe you need to install xserver-xorg-input-evdev
sudo apt-get install xserver-xorg-input-evdev
After that execute
sudo cp /usr/share/X11/xorg.conf.d/10-evdev.conf /usr/share/X11/xorg.conf.d/45-evdev.conf
and reboot.