You said you put this in Windows command prompt:
avrdude -c usbtiny -p m644 -F -U flash:w:xxx.hex
what is xxx.hex? It should be the actual name of the firmware you want to upload. In your case, firmware2.0.2.hex
There is a README.txt in the folder of each firmware. Please, read it.
To answer your last question: your controller should still be alive. It appears dead probably because you uploaded something wrong. Just try to upload the correct firmware and it should work again.