Texture Bombing not working if I change the UVs TextCoord or Tiling (S) size

I’m not sure if it’s a bug or if I’m doing something wrong. If I don’t change the TextCoord like in the number 1 screen, the texture bombing works and I can have a random tile pattern (that’s what I want), but in number 2 screen, if I change the TextCoord, or if I change the Tiling (S) parameter inside the texture bombing, the texture bombing doesn’t work, and I can’t have a random tile pattern. In the second screen I end having a repeating pattern.