Joe Crawford the creator MmmmTools have included my script k_progressiveRendering as downloadable package in the MmmmTools.
The tools automate the download and the installation of the k_progressiveRendering script, but it does not include the Render Window icon implementation.
MmmmTools is a really nice package of extremely usefull scripts to help speed up your work in Maya. I suggest taking a look at it. http://mmmmtools.celestinestudios.com/