Ok i got sony vegas movie studio...

I tried saving it but it only saves like 5 seconds??
Does it matter of one clip is mp4 and another is divx??

Hi there noob!
What you are saving is basically a list of your edits, effects etc. It is NOT saving a new video - for that you need to render (or click Make Movie as you're using Movie Studio)
This is one of the great things about Vegas and many other packages. You can create as many different edits as you like and view them (or demo them) in the preview screen without taking up much space and without having to wait hours for a render.
As for your second question - no, it doesn't matter. Vegas is what we call "format agnostic". t will work with just about any format your computer can read. You choose the output format when you render.

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Tim