You would need to use an ActionScript FLA, not an HTML Canvas one. If you're using an ActionScript FLA you can go into Publish Settings and choose GIF Image from the Other Formats list. If you click Publish you will get a GIF file of the frame that is showing at the time.
You can goto File menu > Export > Export Image and choose the filetype as GIF to export.
Yes! That is it. Thank you so much.