Puzzle 7-8

puzzle bonus 7-8 how????help please

i know the original post has been done long time ago but, may be this will help new comers.
here u go, the trick is to keep the multi-color to the last. u can switch balls using the right click.

1- switch to red and shoot beside the red on the left hand side (between the white and red)
2- switch to red and shoot the two reds on the right
3- switch to red and shoot the two reds u previously put aside on the left
4- change to orange and shoot the 2 orange
5- change to violet and shoot the 2 violet
6- now shoot the multi color between the two blacks

you are done

enjoy and have fun