Problem with the snow tutorial+mask

Hi all,
I’ve got a problem masking the snow effect by this tutorial : [size=2][color=#004080]http://www.kirupa.com/developer/mx/snow.htm[/color][/size]

[color=#004080][size=2][color=black]when i place the MC in my movie it runs good[/color][/size][/color]
[color=#004080][size=2][color=#000000]but when i mask it - its everything but good.[/color][/size][/color]
[color=#004080][size=2][color=#000000][/color][/size][/color]
[color=#004080][size=2][color=#000000]this.help(SyPhEx) ?[/color][/size][/color]
[color=#004080][size=2]:crazy:
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