I am submitting this to help a friend in her digital art class.
Is there a way to unpublish a flash file so that I can go back to working on it? Sort of like going back to revisions in word and being able to start back at any of the revisions.
Any help will be greatly appreciated.
If you're talking about having the FLA and you want to open it and revert back to some older version of the FLA, no you can't do that. Managing versions of FLAs is up to you.
If you don't own the SWF then decompiling can be copyright infringement. If you do, it doesn't always work. There are many settings stripped from SWFs that FLAs have (graphics/audio compressed, etc).