Can you run command prompt as Administrator? then go to the unzipped folder, and execute the following:
devcon.exe install vmlitediskmp.inf root\vmlitediskmp
and post the output.
C:\Users\randalls\Desktop\vmlitediskmp>devcon.exe install vmlitediskmp.inf root\
Device node created. Install is complete when drivers are installed...
Updating drivers for root\vmlitediskmp from C:\Users\randalls\Desktop\vmlitedisk
Another thing, is it possible your PC is configured to block unsigned device drivers? If so, it may not allow to install our drivers.
While I'm not an expert on Windows 7 (having used it for less than a week), it is my understanding ALL copies of 64 bit Microsoft Windows 7 (and copies of 64 bit Vista. I believe) require (expensive to get, $500+ a year) signed drivers.