We have decided/realised that it’s ok to mention the method of getting P4 for free. Ubisoft no longer sells P4, so people getting it for free are not taking money from the company. Also, despite Ubisoft knowing full well that the 4.2 patch made the demo into the real game, they still offered the 4.2 patch for download for years, until the link broke a few years ago. If they weren’t bothered, we shouldn’t be.
Installation of the Petz 4.2 patch will turn the demo into the full version and can be googled and downloaded, but PetzA does the same thing and is probably safer. PetzA can be downloaded from Sherlock Software.
To clarify – the only form of Petz 4 you can download legally and safely is Petz 4.1 Demo. As well as being a Demo, Petz 4.1 does not work well on XP and later machines. You patch it to 1) make it the full game and 2) make it work on XP and higher. So your process is:
1) Install Petz 4.1 Demo from cnet
2) Install PetzA from Sherlock Software to apply the 4.2 patch
3) Open Petz.