This same link appeared on the Mazda 6 forum and I shall repeat what I said on that occasion.
"I would also caution members to think carefully before undertaking any "Hack" of their CMU, especially as the information in the link, is not, from a genuine Mazda publication."
Especially given the statement on the first page "The purpose of this website will be to document and archive the progress people have made with hacking the Mazda CMU infotainment unit".
The person who posted it on the Mazda 6 forum, did so as only his second post on the forum. When challenged, he abruptly left the forum. That in itself raises a few doubts.
Considering all of the well documented problems that the Mazda Infotainment system has, I personally, would be very suspicious about following any of the advice on that web page.