I files one here:
http://www.displaylink.com/support/ask_question.php
Yes... I'm going through the paces... the support guy is nice but he's as clueless as i am.
I do have some new details.
1. If i shutdown all displays turn off as normal.
2. If i put the laptop to sleep, the display using displaylink via usb displays a "Signal error".
As it stands, it seems that if the power is not completely off the usb displaylink still expects some kind of data from the port.
Still the monitor on the usb displaylink will not go in standby when the computer is on.