Hi!
After updating to Windows 8.1 Enterprise my extended monitor is on but shows a black screen, my issue seems very similar to this thread that seems to have been solved by updating to beta Nvidia-drivers:
http://www.displaylink.org/forum/showthread.php?t=61793
The only difference I can think of in my case is that i primarily use an Intel-card. To be more specific, I have a Nvidia-chipset but it's not connected to the ports of my laptop, it can only be used for accelarations within programs.
I have followed the steps in "Exclamation HOWTO: Debugging issues on Windows with DisplayLink" and supply the Support Information.