I seem to be having an issue with using Railclone Color. I have used Forest Color many times with no problems, so I am acquainted with the map and what it's supposed to be doing.
I have attached a test render for you to see, along with my settings. I had 5 different wooden shingle maps attached previously (with tickboxes on), but for the sake of this test I have assigned 4 different colors instead. It seems like only the first color is ever applied. Also there is no difference applied when I tick Enable Tint with random strengths of grey and multiply assigned.
The roof itself is very simple - I went by your latest tutorial. There are two very basic shingles applied - one full width and one half-width. I haven't changed material ids on base objects.
What am I doing wrong? Perhaps a setting in the RC object itself?
Let me know if you need anymore info.