Ok, I want to purchase Gravity Forms, but im kinda confused on a couple things. One, im so use to just downloading plugins from WP's plugin section that I don't know how to add this plugin to my website after purchase... Second,i only have one page. I only need the ability to make forms and use Authorize.Net as my processor...Will i have to purchase the Developers account for that or could i purchase one of the others and by an add on?