Rebol is dead. The closed source is not maintained and was released as abandonware.
A few people have tried to keep it going, there is even a version for Android, but there have been no commits for over a year.
Huh?
Rebol 3 ("alpha version") is open-sourced under Apache 2.0 license; most recent commit is dated Mar 04 2014; not quite yesterday, but certainly not "over a year ago". See:
https://github.com/rebol/rebol
As to Red, it is a totally separate project, kinda rewrite from scratch of Rebol (started when Rebol 3 was still closed source and seemed dead), and although still not complete, looks very lively:
-- see also the pretty status/completion tracking graphs for Red at: