I reported this as a bug in CC, but maybe I'm not the only one with this problem or someone can tell me what I'm doing to trigger it.
Steps to reproduce bug:
1. Open my complex SWF with a single exported MovieClip symbol
2. change something
3. set publish to SWC only
4. publish
5. include the SWC in a FlashDevelop project
Results:
About a third of the time, the new SWC contains no exported symbols.
Expected results:
SWC should contain my one large exported symbol.
Workaround:
Immediately publish a second time. Usually the exported symbol will appear in the SWC the second time.
If not, create a new dummy exported symbol in the same FLA and publish again. Changing the list of exported symbols seems to reset something.
Deleting the SWC before creating it, unhooking it from FlashDevelop, or closing FlashDevelop do nothing.