I am doing some rockets in Motion and I can't quite get them to work properly.
When the rockets hit their target, a plane, I am attempting to stop the particle emission and leave the rocket exhaust in the air..
Also I am trying to get the particles to stay on the path as the emitter moves through the scene. Seems that even old particles are still attached to the orientation of the emitter. Rather than being completely unrelated once they are emitted.. For instance.. How would I do a spiral trail? When I move the emitter ALL of the particles of any age re-orient themselves to the emitter's orientation.
just guessing on this one because its difficult to know exactly what you are looking for.
#1 sounds like you need to set some keyframes on BirthRate, Life and Speed in the Inspector of the Emitter to get the particles to hang there after they hit the destination. If you are really trying to freeze them in space then add a Drag behavior to the cells. That should come close.
As for #2, I'm not sure if this does what you are asking but try the Attach to emitter slider in the Emitter controls in the Inspector. you could also try the paint tool. Paint tool is somewhat of a more controlled particle system.