Hi there, have a problem dealing with sprites...

I made an animated sprite in pcx format and imprted it into the game. I open the scripts and intend to assign an action to the sprite in order to control the frame movements.

Take at look at my action:

action sprite
{
my.transparent = on;
my.alpha = 100;
while(1)
{
my.frame += 1.5 * time;
if (my.frame > 24)
{
my.frame -= 24;
}
wait(1);
}
}

But the problem is, when I attach this action to the sprite, build it, and run it, I got a pop up error message saying "<SPARKS+24.PCXSPRITE>: Can't open file" what is wrong here? By the way, my sprite name is sparks+24.pcx Thanks alot!