FMX help with multiple duplicating clips

I just finished the Create Falling Snow tutorial easily enough.
I wanted to modify it for my own purposes by having the snow stop at the bottom and gradually build up while continuing to fall. My first step was to get the snow to stop at the bottom and stay there, but then of course there was no more falling snow. I figured I would just add another movie clip with similar code on another layer so that clip would duplicate and continue falling while the other fell and accumulated on the bottom. When i did that however, the new clip wouldnt duplicate, just one single entity that drifted down. Any ideas as to what i’m doing wrong? I’ll include the fla if its too confusing.

well its not entirely accurate but u could just have a fallenSnow mc and have like 10frames in it of snow gradualy building up. then each time a snowflake hitTests the fallenSnow mc it could just go to the next frame with more accumulated snow.