The Mirror Driver SDK contain more info and samples about mirror driver usage.
More info SDK

How does it Work?

The Mirror Video Driver is a driver that UltraVNC (for instance) can use to be quickly and efficiently notified with screen changes. Using it on an UltraVNC server results in a excellent accuracy. The video driver also makes a direct link between the video driver frammebuffer memory and UltraWinVNC server. Using the framebuffer directly eliminates the use of the CPU for intensive screen blitting, resulting in a big speed boost and very low CPU load.

Supported OS for mv2 mirror driver?

win 2000 
win 2003
win 2008
XP
Vista
Win 7

Installation

If you have a previous version installed, it is recommended to uninstall it first, by doing the following: setupdrv.exe uninstall
Installation is done by setupdrv.exe install
The program setupdrv.exe is located in the folder you've chosen during the driver installation.

Manual Uninstall

1. net stop vnccom (stop communication manager service) Driver mv2 doesn't use the vnccom , only needed with the old drivers
2. Under XP: Control Panel ⇒ System ⇒ Hardware ⇒ Device Manager ⇒ Display Adapters ⇒ Uninstall mirror driver.
   Under W2000: W2000 does not allow video drivers to be removed while running.
   Trick: Remove vncdrv.sys (that is in system32/drivers), and reboot. You now can remove the driver the same way as with XP, via the device manager.

Upgrading issue

For each version the vncdrv.sys and vnccom.sys are a pair. Vncdrv.sys is a kernel driver, so can only be unloaded on reboot. After upgrading the driver, vncdrv.sys is still the old version, but vnccom.sys is already the new one. Switching of vncdrv.sys is done on reboot. Don't use the driver before you reboot.