Flex Style preloader in Flash?

Does anyone know if there is a flex style preloader option in flash?

I dont mean using a loader swf to load another bigger swf, but an actual loader that works before the swf is fully loaded

I have a flash project with lots of external classes (like tweenlite/queueloader/hive) and they all sit on the first frame

using a loader swf is also counterproductive because i’m using loadvars passed from JS.

I guess i’m a bit let down cause flex has this out of the box and in flash we have to reinvent the wheel

Anyone has any tips?