The download link is still out there, by the way. You won't find it with a search engine. You won't find it on the dark web. But if you ever see a file called core_crossing_v0.9.7z on a site that shouldn't exist, with a timestamp from six years ago...
On the third day, he ran his integrated test build. A simple scene: a red ball, a blue ball, and a seesaw. Drop the red ball on the left side, the blue ball launches into a target. Simple physics. But with Core Crossing enabled, the player could branch at the moment of impact. In Branch A, the red ball was heavy. In Branch B, it was light. In Branch C, the seesaw was made of rubber. Core Crossing Free Download
He clicked download.