How do I download free Petrograph software?
You can download the application from the developer's website. I have downloaded and installed it. The software works fine and it's free. There was no nag screen or pop-up saying to register. Visit the official website to download it.
Official website: http://accounts.unipg.it/~maurip/SOFTWARE.htm
Direct Download URL: http://accounts.unipg.it/~maurip/Data/PetroGraph2beta.msi