Particles are a little tricky.
Do something like this.
PHP Code:
function onCreated(){
with(findimg(200)){
image = "block.png";
with(emitter){
speed = 5; //The movement speed
emitautomaticly = true; //Makes it emit by its self
lifetime = 5; //How long a particle lives for
//look up addlocalmodifier in rc script help I can't remember it.
addlocalmodifier("range", 0, 1, "alpha", "subtract" 0.05);
//It's something like that
emit();
}
}
}
Just play around with the add modifiers and change the variables you're editing until you get something you like.