On V-Ray 3 I don’t manage to put a color outside the decal. I did put a bitmap in the diffuse color, I uncheck the tile option, change the “no UVW color” and I didn’t get a result. Just black, with crop or place there is sometime the red color.
I tried to post something on Vray forum with no luck. I didn’t find the +new Topic !!! Not a very clear forum.