I made a SWF with some png's, but I didn't realize that shrinking the png's would make the graphics look shotty. I want to have straight non-pixelated lines, so I updated the png's with a smaller size. Now, is there a quick way to revert the graphics to their original sizes? Or do I have to create the SWF all over again?
Select the item and do Modify > Transform > Remove Transform (Command + Shift + Z).
It will restore it to the original size.
Also, if you turn on check ‘Allow Smoothing’ in the properties for the PNG it will not look so pixelated when you scale it down or rotate it.
I haven't used Flash for a bit - but I remember there was an "update" command available for images in the library (properties, or right-click?). In order for that to work, though, you would have to actually overwrite the original image files with the new ones (same names). Doing that will allow Flash to see that they have changed. I don't know of another way, sorry!