Keyboard shortcuts don't work

Your gnome-settings-daemon isn't starting on boot, for some reason. The workaround to that is to add gnome-settings-daemon to Startup Applications or add it as a .desktop entry, into /home/yourusername/.config/autostart/ directory. The .desktop entry could be named gnome-settings-daemon.desktop and look something like this:

[Desktop Entry]
Type=Application
Exec=gnome-settings-daemon
Hidden=false
Name=gnome-setting-daemon

This is my guess on why that daemon isn't starting: Ubuntu 15.04 , from what I've heard, has switched for different system for starting processes at boot - there used to be upstart and 14.04 (which is what I use) has that. Meanwhile 15.04 uses systemd . My guess is that this transition has broke some things, but hopefully by the time we get to next LTS release, everything will be fixed