If you are using Flash CS4 to draw transparent graphics and intend to use them in photoshop later, think twice there is a problem here. Some time Flash CS4 adds some black edges similar to matte edges in GIF, even if you select PNG 24-bit with Alpha Channel. This problem got introduced in Flash CS4, hope Adobe fix it soon. any way solution of this issue seems to be simple, but it’s a work around.
First break apart all text in your graphic, remember to break apart text completely you have to break apart twice. try exporting now, most of the cases this should solve your problems, if not then go ahead and break apart symbols in your graphic. exporting now will give to smooth edged PNG. But by breaking symbols to shapes will often you loose shape arrangements, things behind can come forward, or thing front can go backward. To avoid this situation before breaking apart select all elements in your graphics and “Distribute to Layers” Ctrl+Shift+D, should do that, by doing so every shape, element will get a layer for them selves, breaking apart now will not loose arrangements.
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