Step 4 is a combination of 2 and 3 (to avoid the renaming to zip step). Requires that you copy the idesettings.txt to the arduino directory too. I guess you get the "reinstall arduino" error right?
Will the fix for the pretty icon work with the new software (V1.5)? And if not, would you mind making it work again http://arduino.cc/en/Main/SoftwareDue