You can download Nanosaur 2 for free from these sites:

Mac: http://www.pangeasoft.net/nano2/downloads.html

Windows: https://www.myabandonware.com/game/nanosaur-2-hatchling-ge2

When prompted to register your copy of the game, enter the following information: Reg. name: Pangea Serial number: 3163-5283-3562-9843 Order number: 1