"I can download your PSE 4 Booster elements download (http://hiddenelements.com/downloads.html), but which of the old other downloads can still be used? A summary for each PSE tool download might be helpful."
I am in the midst of writing the book and editing the tools for Elements 4 and expect to be done within a week. I will begin updating the site in the new year, with the tools and new freebees. Each of the sets already has a listing as to which version it works with. I would rather put up complete sets than sets anyone has to hack, and it is easier to do that than list what will and won't work in each set (and less confusing). The short version is: anything that required the curves interface, color balance, guides, channel mixer, and a few other of what were standard interface items no longer work. I will have work-arounds for everything in the new book.