Question about using this product

[sheicgirl]

Hello,

I'm new to flash and new to this product. I have several images that I
would like to transition on a web page, sort of like what you see
here, http://www.thebuildersnewsletter.com/ See how the image in the
middle changes after a few minutes? I want to create something like
this. I am trying to figure out how to do this with this program.

Also, when I insert my png images in to the program, they look all
pixely and distorted but they don't look that way if you view the file
outside of the program. Is there a reason they look terrible?

Thanks for any help you can offer.