Adobe Flash CS6 Image Filling Preloader not working?

Question

I'm trying to make a flash preloader using a image that slowly fills up.
I used the tutorial on this site:
http://flashexplained.com/preloaders/creating-a-preloader-for-your-flash-site-using-the-im age-of-a-bottle-and-a-rectangular-mask/
I tried following the instructions until I finished and saw it wasn't working correctly. When i tried testing by simulating internet speed the screen showed blank for the first few seconds until the image loaded already half-way filled up. It's supposed to load completely transparent and slowly fill up from the bottom.
So, I downloaded the source file from the tutorial link i showed above to see if i had dont something wrong while following the instructions only to find it happens there too... I uploaded a video of my screen on Youtube to show what is happening to me:
Does anybody know why this is happening? Could it maybe be because I'm using the newer Adobe CS6? Any help is appreciated.

Answer 1

The code is:
stop();
rectMask_mc._height = 1;
this.onEnterFrame = function():Void  {
          var loadedData:Number = this.getBytesLoaded();
          var allData:Number = this.getBytesTotal();
          var percent:Number = Math.round(loadedData/allData*100);
          rectMask_mc._yscale = percent;
          if (loadedData>=allData) {
                    gotoAndStop(10);
                    delete this.onEnterFrame;
I did a little testing and noticed when I deleted the line "rectMask_mc._height = 1;" it still does the same filling animation I got before that starts halfway.. so I'm guessing that command no longer works in CS6?!
Edit:
I just tried the "rectMask_mc._height = 1;" command by itself and it works...
I'm sorry im just new to Flash, trying to learn the basics and reading up on tutorials but they are all outdated so I'm trying to figure out whats the problem with it not loading with its height at "1" then filling up when I'm using the entire code. The height command only works when I delete the rest of the code.