I found a bug in release R82 which makes my game unplayable. It appears that when a physics object has more than 1 frame of animation the physics completely breaks down. Here's a capx that shows the problem. You can press "T" to toggle the sprite between a 1 frame animation and a animation with more than 1 frame. Try moving the ship forward and then toggling on the animation to really see the problem.
http://dl.dropbox.com/u/28484936/ship_shooter_animation_bug.capx
Here are my specs:
Windows Vista Home SP2
64-bit
GEForce GTX 560
Chrome 17.0.963.79
<font size="1">Edit: Corrected link to capx file.</font>