Is there any limitation on the number of added child in a movieclip?

Hi,

        My application is a self-defined streaming player page. I would like to show the information of a series of video clips on the time buffer bar of my player as the following figure. The blue parts are the valid video clips. What I want to implement are that a thumbnail will show when MouseEvent.MOUSE_MOVE is triggered and the streaming will go to the right time when MouseEvent.MOUSE_DOWN is triggered. The information of the video clips(start time and end time) is received from remote server, so I need to generate the blue bar dynamically. My codes are as follows,

for(i = 0; i < pieces.length; i++)

{

  if(pieces.end > beginning)

                    {

    var wid:Number;                  // The variable to decide the

    var rect1 = new Videoclip;   // The class of video clip, which contains the blue image

    var xx:Number;                    // position of the blue bar at x axis

    if(pieces.start >= beginning)        

    {

      wid = 840 * ((pieces.end - pieces.start) * 1.0) / ((ending - beginning) * 1.0);

      xx = 840 * ((pieces.start - beginning) * 1.0) / ((ending - beginning) * 1.0);

    }

    else

    {

      wid = 840 * ((pieces.end - beginning) * 1.0) / ((ending - beginning) * 1.0);

      xx = 0;

    }

    rect1.x = xx;

    rect1.y = -1;

    rect1.width = wid;

    rect1.addEventListener(MouseEvent.MOUSE_DOWN, progressClicked);  // add two event listener dynamically

    rect1.addEventListener(MouseEvent.MOUSE_MOVE, thumbnail);

    mcVideoControls.mcProgressFill.addChild(rect1);                                      // mcVideoControls.mcProgressFill is a movieclip symbol

                    }

}

I want to ask if there is a limitation of added child for a symbol of movieclip; also, I wonder if generating an event listener dynamically is a good idea. Thanks.