The first thing to remember is to never open a zip file in your main (root) area... always open it within a directory, either an existing one, or one you've made just for this zip file. Once you've beamed a Zip file into your account, making sure that you name it with the proper .zip extension, log in and go to the directory in which you beamed the zip.
If it is a valid zip file, you will see "unzip" to the right of the file. Click it and it will open the zip file and put all the components into the directory, also leaving the original zip file there. Once you've checked all the components to make sure everything is there, and there are no problems, you can delete the zip file itself.
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