what random effector? I don't see anything with that name in XP, but i'd like one. in the group settings, or if you don't have a group the emitter, you can set random size with the radius variation.
HI,
Maybe you could use the distance of the camera to drive the panel opening for each clone.
This is one way with mograph, I don't know if you can move your door with mograoh effectors but here ya go.
doors.c4d
Hi,
you might try switching particle groups from spawning to not spawning after 60 frames, then the modifier keeps working on new particles.
spawningc4d.c4d