The base model attached to the Frozen Sigil unit is the "Snowflakes_Base" model, the model uses "effects\Snowflakes.mdl" in several nodes that create that snowy fall effect. The "Snowflakes" model must follow the "effects\Snowflakes.mdx" path.
Ghan has said he has fixed this. Monovertex please confirm this fix. This was only a problem with people that had signatures in the upper levels like not the special members but the respected members.