You can combine your movies by opening them all in flash, then copy frames from each and paste into single movie. Your Library should update automatically.
<EMBED src="/cgi-bin/ubb/Members/sigs/00000549.swf" quality=high WIDTH=400 HEIGHT=80 TYPE="application/x-shockwave-flash" PLUGINSPAGE="http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash"> </EMBED>