Action For Empty Object Appears Not to Play in Game Logic Layout, DOES Play In Default Layout .blend file has:
      - two Rigid Body Mesh Collision Proxies (A Foot: Ankle to Ball &amp; Toes)
      - A set of 5 Empty Objects That Are Animated to Control the Collision 
        Proxies.
      - Two of the Empties have Locked Track Constraints...(is this the issue?)
      - A rigid body plane (Tile Floor) to act as ground 
      - a few (650) rigid body 'Sand' particles intended to simulate the 
        behavior of sand.
      - Short color-change Python script

Issue: In Game Logic Layout, the actions for some of the Empty Objects
       appear NOT to play, while in Default Layout everything works as 
       intended.

Fixes Tried: Everything I can think of, so it's probably something obvious!

Goal of project: To help beginning trackers learn to read tracks.  The 'foot'(collision proxies) are to be animated, and should leave a realistic track in the 'sand'
RESOLVED!
   I had the collision proxies set up with Empties using Locked Track Constraints.
   Didn't know regular constraints and BGE aren't happy together. 
   Switched to Rigid Body Constraints.
   Now everything seems to be working correctly in both Defailt Layout and Game Logic Layout.
Thanks!