I looked through the forums about this topic. There was a discussion a lot of speculation and no solutions. Flash C6 was the last version the ability to import a swf into a fla development file. It seems as the common stance on it is "hey if you didn't save your previous version, oh well". There are 2 questions I have for an Adobe representative:
1. Why was this feature taken out. Its a step back, not forward.
2. What is the current solution for this to be accomplished.