So this has been driving me nuts all day. I made a comp alot like the nano tutorial, and all was good in the comp, but then i realized that the flight of my emitter light was not correct on the z space to wrap around my 3d text in my main comp... i recreated this "comet" like particular effect in my main comp so i can properly adjust its z space animation. For some reason... when i select custom and assign my comp for it the comet disappears. If i select a preset like sphere or cloudlet its fine but for custom it totally disappears. (note. i am also obscuring the particualr comet path with my 3d text layer) Can someone please shed some light as to why this custom particle wont show up?
First, check your custom source settings. It may be that you have it set to the default of current time, and your custom source is only a fraction of the time of your comp. It is hard to tell without looking at your comp. That would be my first guess.