Flash catalyst and Flash Builder round tripping for complex applications

Can anyone give me some tips for round tripping between flash catalyst and flash builder for complex applications that uses components not supported in flash catalyst?

Let's say I have built my design in flash catalyst and have implemented transitions and lots of animations.

How can I bring this into flash builder and add a calendar component (which is unsurpporte开发者_JS百科d in flash catalyst)?

Since the design in flash catalyst represents the main application, I don't think it would be suitable to turn it into a component. The calendar component would need to sit in the main application.

Any suggestions appreciated :)

EDIT: I am using flash builder 4.5.1 and catalyst cs 5.5