Enable the Animation.
Animation will help you in better understanding of the working of your system and circuits. If the animation is enabled, you can see the current flow through the circuit and see the animated components. You can enable the animation by toggling the animation button:
If you compare the simulation with and without animation, it is clear that for a good understanding of a current flow in, for example, a recitifer, animation can be very helpfull:No Animation
The parameters for the animation can be set in the animation properties dialog box that can be opened by clicking the rainbow on the right side of the Caspoc window. The color of the current, voltage and signal levels in the block diagram are defined in the animation properties dialog box that can be selected by double clicking the rainbow on the right side or by selecting Options/Animation.