They should've just move on to Photoshop or something, that software got more accessibility to editing stuff comparing to Algodoo. They really need to know that Algodoo is a 2D simulator, not an Art software
ooh, now I understand.
I program to box to turn red and automatically turned into barriers if the boxes collide each other. The road is turned into a killer so that it would prevent the boxes from colliding each other and turn into a barrier