Problems and Limitation

Although the code successfully generate objects which are exported by "Rib" format, and also it has some features to control the randomness and variety, it needs to develop more in order to behave what I expected.

1- This code works with "Nurbs". One the other hand my 3D character, which was chosen for animate based on actor act, was "polygons". I had to use 3D model, because of tracking the skin. Consider that the imported camera from nuke isn't good idea, because the perspective of pimples may changed. Hence, I animated the 3D character and then I selected two arrows of edges, which are located at effected area by disease. I convert them to curve and apply loft to them in order to make nurbs plane which is animated based on polygons character.

2- It should be group projects, due to the 3D charcter had to modeled, textured, rigged, and animated by a professional artists. I did all part by myself so It wasn't perfect and I couldn't use it for tracking.

3- The pimples should appear with a low radius and then increase by gray-scale's level. This helps to have gradient of radius at the border line of texture, but I haven't time to develop it.

4- In order to see the border of texture by secondary geometries I had to decrease the radius and also increase the number of pimples. Although it possible to do it, the render times increase too much. 

Conclusion

At first I had better to spend time thinking about my idea, and anticipate projects problems may I face to. Although I kind of fail in this projects, I learned a lot. I definitely  will develop this code in future. Working with MEL caused some rather difficult situations which needed a small workaround but since I see it as a learning experience it was still fun to find the right solutions to the problems.