I can help a little here.
	Code:
	/*0020*/ sint32 animation:10,     // animation
         		delta_heading:10,  // change in heading
         		padding0020:12;   // ***Placeholder (mostly 1)
 This is a bit packed signed integer 4 bytes long.  that's 32 bits.  The first 10 bits are the animation, hence the animation:10, the second 10 is delta_heading and the last 12 is padding.