Having played with the spiral examples (here viewtopic.php?f=55&t=1329), I see that Sparkle needs a Delay parameter. It should allow to start sparkling from a certain moment (like in Ballistic). The matter is that at the first frame of the animation, the initial particles just fly away from the spiral (see spirals2.wz4) which makes me think that Sparkle picks up particle initial position from Lissajoux and no direction info.
Delay parameter might eliminate that. Besides it would allow for easy fireworks effect without looping emitters. What do you think?