Did you ever find a solution to this? I'm having the exact same problem now. If anyone has a solution I'd love to hear any other ideas!
Sorry to take so long to answer, but I was in the middle of a huge amount of work.
We found 2 ways to do it.
The easy (not 100% precise):
1-Export your animation in SWF (this will Flatten the symbols)
2-Re-import the exported SWF on Flash (this tends to be buggy. Sometimes, Some frames are imported with errors). All frames will become keyframes.
3- Export FXG of the frame you need.
On this method, sometimes you have to fix the drawing on Illustrator. And Masks are always a problem.
The hard way.
1-enter the symbols (all levels of it), and turn the tweens into keyframes.
2-Apply all masks (cutting the drawings)
3-Turn all drawings to unions. (Its a bit tricky, because sometimes, when you do it, Some images change order (front/back).)
One test you can do is to go to the top level and start to break apart the symbols (CTRL+B). If any of the drawings change, go bak and repeat the steps above. You should be able to break apart all symbols until all of the parts are simple drawings or unions.
This way Flash can export any frame to FXG. If you forget any drawing or tween into any level of the symbol it will not work.
We use a plugin to enter the symbol, keeping the frame, to make it easier to work (without the plugin, everytime you enter a symbol, you will be back to the first frame)
This method worked fine, on simple scenes. On complex scenes (with several nested symbols) it's easy to forget something and get a bad result, then maybe the easy way may be more effective. It is faster to fix some part of the drawing than to find out what is missing to be done.
I think I didn't forget any step. Sorry if I did.
Best regards and good luck.
Thanks for your help! We've been doing things 'The hard way' as you put it, breaking all the symbols one layer at a time and working though . . . Its good to see other people having the same issue, hopefully in a future version they'll be a fix or a new way to export vector sequences!
Flash Pro CC 2014 (v184.108.40.206) is now available for download via the Creative Cloud App and Adobe website.
We have added SVG Export feature to Flash Pro with this new release. You will now be able to export out vector content from the selected frame as an SVG image that can be opened directly in a Browser and even imported in Adobe Illustrator.
SVG Export option can be accessed via the Publish Settings as well as via File Menu > Export > Export Image option.
Along with this, we have added several new features with this release. Complete list is available at these links: