Software is a bastard when you try doing it for free Popelscan is good, but just for play back and the new version only supports MOT files which is also a bastard! Spaghetti is good and so is laserboy(very old school style, think DOS) wish pangolin would feel in the giving mood and send FB3's to all the needy laserists of the world.......
Spaghetti is a good free, well layed out software that supports ILDA and timelines. I cant remember the site, but take a look on photonlexicon under the programming section and you will find it. It suppoprts the sound card DAC too...