If Firaxis had any sense at all, they would make R & R the new Official version of Colonization, changing the Steam version of the game into R & R.
My understanding is that legally they could do so. Modders of published games never "own" any of their work; ownership remains with the original developers of the game.
R & R is so stunningly superior to the original release that I fail to see any reason why Firaxis doesn't recognize an easy way to sell a lot more copies of an old game than isn't earning them much now anyway.
Why do people so often miss the obvious?