I have found that the Windows 7 drivers are unstable, for best results use a Windows XP operating system and follow this procedure when programming.
Connect the make controller via USB.
Erase the controller by shorting the erase pins near the top left with a reshaped paperclip.
Then unplug and replug in (power cycle the make controller)
If the driver can't be found then manually add it, by selecting "Have disk".
The controller should be detected as "Unprogrammed" when using mchelper and the red light should be on.
Note: (if the green light is flashing I believe this means that it is loaded with the heavy20-1.6.2 firmware and you won't be able to load a program as it is not unprogrammed)
Now it should be ready to program.
Use MCbuilder to load a program.
My next post will cover loading the LedWebServer example code.