Thanks for looking at that code for me!  I was worried about those exit commands.  I think we figured out that there was a loose connection with one of the encoder wires, and it was causing the erratic movement.  My worry now is that if a connection were to get lose while the machine is running, it could destroy itself.  The machine only does one routine, so I can tweak the following error to be as low as possible, and hopefully catch abnormalities, but the motion I was witnessing would have probably not been stopped in time.  Do you have any suggestions for sensing something like this? 

Sorry, I forgot to answer that the first time.  We are using a servo setup with encoders.  What you described is exactly what happened to our machine.  There was a loose connection that developed while the machine was stopped, and when it was started up again, the axis in question just started running away.  I guess the reason this hasn't been been a problem with industrial scale machines is that they have linear encoders that can be continually checked against the rotary.
I had an idea that might work for single task automation machines like ours.  If you only gave the machine a certain amount of time to resolve back to its prescribed position when in a stationary condition, that would at least minimize the amount that it could run away.  I was hoping the following code would work, but it doesn't recognize the Dest command. I also get a different number for the Pos command than I get when I run it on the console.  Any suggestions?

#include "KMotionDef.h"                       

main()
{
 float max_time_x = .01;                            //set your max time to allow x axis to resolve to position

 float test_dist = 80;                                             //set your test distance           

 float inv_test_dist = (test_dist * -1);                              //inverse of test distance

 while(1)                                                            //continually run the following check
 {
  if (CheckDone(0) == 1)                                                            //if x axis is not currently in a move         
  {
   if(((Dest(0) - Pos(0)) > test_dist) || ((Dest(0) - Pos(0)) < inv_test_dist))    //if difference between destination
   {                                                                                       //and position is greater than test distance
   
Delay_sec(max_time_x);                                                    //wait for the time allotted
 
    if(((Dest(0) - Pos(0)) > test_dist) || ((Dest(0) - Pos(0)) < inv_test_dist))     //if difference still greater than
                                                                                                            //test difference
               
    {
     Disable(0);                                                      //disable the x axis
   
     Printf("x axis did not resolve in time. You may have a loose connection\n");
    }
   }
  }         
 }
}