After downloading to your computer, go into your forum's admin section, then go to packages, ok, on this page locate the words download packages, see the text box? Beside of it is the word browse, now click that word, it will take you to your computer, browse, or look for, where you downloaded the software, EZPortal. Found it? Good. Now click it, it is now in the text box, look for the word, upload, click it.
It will take a moment or two depending on your connection, but now you should see, EZPortal 3.2 to the right you will see the word, apply mod, click it and it should go from there.