I came across this web site,
and I like the way the main image loads. I appears to me as if
there's a mask being applied, and in spite of trying several
different approaches I've finding it difficult arriving at
something that resembles this.
If I understand Flash correctly you can link several masked
layers to one mask layer, but the mask(s) themselves have to share
the same layer. If all of these small masks are on the same layer
how is that best achieved?