Only from black to white?

So in case anyone is interested I ended up changing the code so that it changes the opacity instead of the color (that way, the color can be changed in the CSS), replace the FadeIn_Ontimer function in the wp-fade-in-text-news.js file:

function FadeIn_Ontimer() {
  if (FadeIn_bFadeOutt) {//triggers if text is visible (FadeIn_Fade = 0)
    FadeIn_Fade-=FadeIn_FadeStep; // FadeIn_Fade+=FadeIn_FadeStep; 0 => 255, black to white; 1 => 0, visible to invisible
    if (FadeIn_FadeOut>=FadeIn_Fade) { //if already at 255, then it returns that it's already invisible (because it's white)
      FadeIn_Cursor++;
      if (FadeIn_Cursor>FadeIn_Max)
        FadeIn_Cursor=0;
      FadeIn_SetFadeLink();
      FadeIn_bFadeOutt = false;
    }
  } else {
    FadeIn_Fade+=FadeIn_FadeStep; // FadeIn_Fade-=FadeIn_FadeStep; 255 => 0, white to black
    if (FadeIn_FadeIn<=FadeIn_Fade) { //if already at 0 (and it does start at 0), then it returns that it's already visible (because it's black)
      clearInterval(FadeIn_FadeInterval);
      setTimeout(Faderesume, FadeIn_FadeWait);
      FadeIn_bFadeOutt=true;
    }
  }
  var ilink = document.getElementById("FadeIn_Link");
  if ((FadeIn_Fade>=FadeIn_FadeOut)&&(FadeIn_Fade<=FadeIn_FadeIn))
    ilink.style.opacity = FadeIn_Fade;
}

(Then you can also remove the ToHex function, which becomes superfluous)
While you’re in there, you can also tweak the speed of the fading effect by changing the FadeIn_FadeInterval number to 30 or 50 (the bigger number, the slower the effect).

Then change the settings in the WordPress interface to:
FadeOut 0 (minimum value of the range, the opacity is set to 0)
FadeIn 1 (maximum value of the range, the opacity is set to 1)
Fade 1 (the text starts completely visible)
FadeStep: something between 0.01 and 0.1, 0.05 works nicely for me

Cheers!