The component scales the contained page by default. You can cancel scaling, by setting the Scale content parameter to false.
When scaling, the component uses information on the size of your SWF file it contains. For example, if your page is empty and has only a small text in the center, the component calculates that the page size is equal to the size of this text field. In such cases you should set the page size by placing a shape or image under its content, the size of which is equal to the page size. You can find an example of this in the examples that accompany the component.