If the screen is frozen and cannot be moved after you uploaded your Flash on the Internet, you should try Test Movie to confirm what has gone wrong.
You have to readjust adequately the setting of layer and frame when bars are going much above the red line. Therefore you always have to hold a firm knowledge of transfer speed and system capacity to create a Flash movie. Dim shows the movie size by the unit of pixel.

If you are using 17 inch monitor with 1024*768 definition, 1024 and 768 means the horizontal and vertical pixel of monitor. So, the 440*250 above corresponds, horizontally to the half and vertically to the one third, of the whole monitor size. I believe you are understood now.

Next, Fr Rate indicates proceeding speed of frame per second. This setting is established in the basic value of 12 in Modify/Movie. You will see no difference in a low class computer, but execute Test Movie in a computer of Pentium II or above, setting the value to 40. Movie will be played in a tremendous speed.
But do not concern yourself much because Internet speed is unable to be compared to that of computer. Anyway, in case your Flash speed is too slow, it might be well to adjust this frame speed a little.

Please note that CD-Rom makers use this option very frequently. Size indicates the capacity of Swf file. You do not have to look into Windows search to get a view on file capacity, for you can verify it here while designing your work.
The part below it is showing loading time and bandwidth is indicating transfer speed. If you are a 56K modem user, set 56K in Control menu and try testing to know how it works before you are connected.

But, this method is a little bit short of precision, use your discretion to utilize this.
Personally I use it for a test when I inserted Preloading scene. Test it after you set 300B or less in Control/Customize.