I tried to use `ColorReplace` to change the colors obtained from `MorphologicalComponents`. However some of the changes didn't follow the rules specified, Is there any reasons?
  
    im2 = Binarize@Import["https://i.sstatic.net/ZDeYq.jpg"];
    im3 = Colorize@ MorphologicalComponents@im2 
    colors = DominantColors[im3, 5] 

 ![enter image description here][1]

Now trying to change the colors accordingly,

    ColorReplace[im3, {
      colors[[2]] -> Red, 
      colors[[3]] -> Blue, 
      colors[[4]] -> Green, 
      colors[[5]] -> Yellow
      }]

One of the changes did not follow the rules specified:

![enter image description here][2]
 


  [1]: https://i.sstatic.net/5gZkM.gif
  [2]: https://i.sstatic.net/aNxL2.gif