Hi jb,
This is most likely a problem with your nVidia settings and monitor configuration.
You have been sent the ReeReal Setup Manual as PDF doc in an email, please follow the instructions in there.
The SeeReal 3D screen is typically used as a second screen in clone or dualview mode.
This means that (depending if your graphics card had two digital ports or one analog and one digital) you need a second analog or digital monitor which is able to display in 1200x1600 resolution.
All you need to do in Vizard is to output in interlace mode, like you seem to have done correctly.
We have made available a free demo collection for the SeeReal 3D monitor at
http://www.worldviz.com/download/index.php?id=19
The demos should work plug-and-play as soon as the monitor is set up correctly and show it's stunning autostereoscopic 3D abilities.
Have fun!
The WorldViz Team