Flash doesn't export nice looking.gif files. You can try to export your animation as a PNG sequence then open that as a sequence in Fireworks(frames will be added automatically) and export an animated.gif from there. You'll have more control (over image(number of colours) and animation(repeats,timing)) for gif export. Another alternative that comes to mind is to use the library to export a decent gif via code, but that's handy if you're comfortable programming in actionscript 3 – Sep 29 '12 at 9:36. GIF is not designed for high-quality images.
Smooth vectors from Flash will end up pixelated in GIFs no matter what you do. Photos and the like will generally look bad because of the reduced palette. Dithering can help, but the end result will still be much lower quality. If you want an animation, you should really be using straight Flash and not GIFs (apart from very simple ones where the quality is not degraded). Or possibly a video format depending on your needs — most large gif-hosting sites seem to have moved to MP4 or WEBM for their primary data.
You might want to check out: Swiffy converts Flash SWF files to HTML5, allowing you to reuse Flash content on devices without a Flash player (such as iPhones and iPads). Swiffy can't yet convert DoubleClick Studio creatives. Swiffy now supports ActionScript 3.0 and external resource loading. On the first link, you will find an upload form that you can use to send the SWF file. In return you will get an onscreen preview of your animation already converted, along with a HTML document for you to download. They do all the work for you.
Flash Player For Mac Download
I've tested it with basic animations and it works great.