Firstly some background information: I have a 4 monitor situation, with varying resolutions - 2 monitors landscape (1680×1050,1920×1200) and 2 monitors portrait (both 1050×1680). Once I'm logged in my resolutions and monitors relative positions are all set up fine, but the trouble I'm having is with the login screen. At the login screen all 4 displays are on, however their positions and rotations are all incorrect. I've temporarily fixed the problem using an xrandr script and a display-setup-script in my lightdm.conf however I'm after a neater solution as this will fail if any monitor is unplugged before login. From guides here and elsewhere, I've found that apparently creating a symbolic link of ~/.config/monitors.xml in /var/lib/lightdm/.config/ should allow my login screens resolutions to follow my desktops resolutions. My problem is when I create the link, I get a permissions error upon login. "Unable to apply screen configuration from /var/lib/lightdm/.config/monitors.xml:Permission denied. I've chown'ed the symbolic link lightdm:lightdm and even tried giving all rwx permissions to both monitors.xml and the symbolic link and finally i've ensured that my monitors.xml is current by deleting it and re-applying my screen settings.
Any idea on where my permission denied error is originating? Any information on LightDM and the /var/lib/lightdm folder (nothing is mentioned about it in the various wikis I've read).