Ok, try adding a few lines:
Code:
Speed       CON 24        ; Smaller=Faster
TracerSpeed CON 15        ; Smaller=Faster 
Left/RightBrightness  CON 255       ; Tracers 
DutyCycleDrainSpeed  CON 30        ; Smaller=Shorter 
TrailBAM_COUNT = 5
Cycle VAR BYTE  ;Count Full Cycles

Main:
    if LoopCount = TracerSpeed then             ; __[ Cylon/Kitt Scanner ]__
      LoopCount = 0
      BAM_DUTY(NextLED)=Brightness
      if TraceDIR then                          ; if scanning left
        NextLED = NextLED - 1
        if NextLED = 0 then
        TraceDIR = 0
        Cycle = Cycle + 1
        IF Cycle = xx THEN
          Do Something
          Cycle = 0
        ENDIF
      else                                      ; else scanning right
        NextLED = NextLED + 1
        if NextLED = BAM_COUNT-1 then
        TraceDIR = 1
       endif
    endif
   FOR Idx = 0 to BAM_COUNT - 1                ; Drain all dutycycles
       IF BAM_DUTY(Idx) > 0 then
           BAM_DUTY(Idx)=BAM_DUTY(Idx)*DrainSpeed/(DrainSpeed+1)
       ENDIF
    NEXT Idx
      pause Speed
      LoopCount = LoopCount + 1
GOTO Main
This should increment your Cycle variable after a full left swing.