I just got my Displaylink today and I am having some issues that don't seem to be addressed in the forums.
My displaylink monitor seems to be working correctly, except it doesn't 'refresh' when something changes on the screen. I can drag something to the second screen, but it won't show up until i refresh the screen (by invoking mission control for example). Once it shows up on the screen I can try scrolling on a web page, or moving the window, but nothing happens, until I mission control and the changes appear. This means my second display only acts as a 'static' monitor right now, since I have to manually refresh the screen.
I made a
video of the issue to help illustrate
EDIT: In the video my main monitor is on the left and the display link is on the right. In the middle of the video i try to click and drag the browser window. If you look closely you can see that after the second mission control action the browser does move to where i dragged it.