The only way I know of to reduce swf file sizes is with the fla file (options you select when you publish) or by making the file as small as possible in the first place (using symbols whenever prossible, not MotionTweening multiple symbols/groups in one layer, changing sound to mono from stereo, etc). Depending on your situation, you may want to use some other animation in place of Flash. Flash files get big easily.
Yep same here. I think thats the only way. Could tell you tonnes on how to keep file sizes small when making a flash file.
Wildform - wildpresenter can resize swf files, the only program i have found so far to be able to do this. not sure of it's compatibility with Linux though.