Firestarter has the capability of converting animated GIF files into Flash™ files, mainly to reduce their file size. Once the file has been converted to a SWF file, you will not be able to add the SWF file to another movie.
To begin the process, navigate to Edit > GIF Converter.
This will open the GIF Converter window. From the window, you can select the input file and the output file. You can also view the HTML necessary to play the new SWF movie on your webpage.