Alison,

I have tried it on two machines, both with Intel 3 GHz CPUs. One (my laptop), has 2 Gb RAM and the nVIDIA G-Force FX card. The desktop has 4 Gb RAM and an ATI Radeon X-1650 Pro graphic card.

Both run your xar file smoothly and export to smooth flash animations.

Sounds like you are running quality equipment, so I can't figure out where the problem might be. This is a serious challenge!

But there are some awesome talents on this forum (I do not include myself in that group, but Soquili definitely falls in that category) and I'll bet it will be solved!
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Will