Swapping Multile Symbols in CS4

Hello.

I’ve searched around and only found 2 extensions that do this, and none of them work for either CS3 or CS4 versions of Flash.

I have over 10 animations each with 40 frame-by-frame bitmap animations (old file… inexperienced at the time… need quick and dirty update…).

Any method I can use to swap multiple symbols over many frames?

Thanks.