Loading-swfs?

Hi!
im just wondering if it is possible making a “loading-swf”, a flash movie which is only a preloader and just change the code for whatever movie id like to load.

and if its possible, a few more questions…
does this mess up _root?
does the movie have to be somewhere on the internet without a preloader so the preloader knows what to load?
can i load it locally?

thanks in advance

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