Here is a cutaway of one "bit" of the CPU. With the ball in this position the bit is in the On, or 1 state. The position of the rocker determines the state of the bit.
This is 1 bit of "RAM", or more specifically, the automated ball loading mechanism. When the switch is in this position, a 1 is stored in the RAM. When a ball rolls over the trap door, it falls through, closing the switch (and removing the bit from memory) and continues through the "FSB" (series of pathways) to the CPU seen above. When all 8 bits of RAM and CPU are in place, the rockers will store the next operation to be loaded into the CPU, if you follow me :P
Though the individual components are quite small, combining enough of them together produces a very large k'nex computer. This view is from the bottom looking up. The dense diagonal row of pieces in the lower right is what is completed of the CPU. The arrows connected to each bit represent either a 0 or a 1 (they are all set to 0 in this picture). Above the CPU is the FSB if you will, though it is really just a series of vertical chutes that connect each bit of RAM to its corresponding CPU bit. The dense area at the very top is the RAM. The chain lift to the left brings the balls up to the top of the computer one at a time and they are delivered to the CPU in a precise order as determined by the switches in the RAM, which were initially set by the users input. Not shown in this picture, a series of very long linkage rods connect each key to the bit of RAM above, allowing the user to input calculations into the RAM directly for later computation. I'm sorry if this is hard to follow, when it is completed I will make a video so it makes more sense.