How to migrate/upgrade old flash designs to the lastest version?

Hello,

I’m new to Flash and I was wondering if there was a way to convert, migrate or upgrade an older version of a flash design to a newer version.

For example, I download a FLA that was developed in, lets say, Flash 6. I try to rebuild it in Flash 8(professional). But, when I try to view it/test it in Flash 8, I get an error message or the animation does not work as it does in Flash 6.

Thank you very much,

Richard