Why does Motion suck?

Motion is possibly the most unstable application Apple has ever written, next to Leopard. I created a very simple 3D project in Motion. It consists of a gradient background, 2 particle emitters (one that was included with Motion), a small Logo object, 4 lights and one static camera. Motion was fairly stable while building the project, crashing only a few times. Upon completing the project, I rendered it a few times to make sure the look and motion was right, and it played back fine. I tried to export it using the animation codec...it crashed the app and OS after 5 minutes. So I tried exporting it using Compressor instead...again, crashed the entire OS turning the screen black. Now, when trying to open the same project, I get nothing but an empty viewer...the project won't display anything but a black screen, and when I attempt to turn off a layer or change ANYTHING for that matter, I get the spinning beachball forever and I have to force-quit Motion. This makes no sense whatsoever.

So, I ask the question...can anyone explain to me why Motion ***** so bad and is so completely unstable? Why is it doing this?