This is running 12.04 on a Mid 2010 with Nvidia GeForce 320M and a USB to DVI displaylink adapter.
I looks like it is almost working, does anyone know why it is turning grey?
Here is a video of what happens : youtu.be/wEgFKzgoFrE
Here is my /usr/share/X11/xorg.conf.d/52-displaylink.conf : http://pastebin.com/WBnNgHwf
Here is my /var/log/Xorg.0.log: http://pastebin.com/KUzhLNU7
Here is the login screen: i.imgur.com/GJmbFrn.jpg
EDIT: The mouse cursor can travel across all the monitors
EDIT2: middle monitor is displaylink
EDIT3: I can right-click on the greyed out screens and change desktop background and bring up a window, but it will not drag between video cards
EDIT4: running killall nautilus removes white screens, still unable to drag between video cards