for us simple apes.
here (http://www.kubrick2001.com/)
I was going to watch that.... but it was too slow and I got bored :(
Pity they havent read the books cause they got it all wrong...
HAL went mad because it was given contradictory programming before it was sent out. It certainly didnt have an intention to eliminate the ships human crew as such but the mission was given top priority and it had to try to make sure that happened.
As for the rest of it the cubes are computers/builders under the control of an alien computational machine. It didnt understand what was happening either.