I found this tutorial as I was painstakingly trying to put ash on top of and around an object with a simulation. I was able to extract my ash pieces from a fractured cube and give them a class attribute before feeding them into the copy to points. Works incredibly well!
IMHO... As a USD management tool. It's great! There is no better tool to visually manage USD anywhere. Not even close... But as a lighting environment, it still needs improvements and better integration with other render engines.