Commando:swfc test1.sc

Input file test1.sc is:

.flash bbox=400x400 fps=50 background=black filename="sprite.swf"
  .circle yellowcircle r=30 color=white fill
  .circle bluecircle r=30 color=blue fill

  .put yellowcircle x=200 y=200 pin=center

  .frame 1
  .put bluecircle x=30 y=30 pin=center

  .frame 101
  .move bluecircle x=370 y=370

  .frame 201
  .move bluecircle x=30 y=30
.end

De output is sprite.swf.