Updates" tab is one of the tabs located below the HTML-Kit main menu (this is the default setting). It makes it easier to find, browse and install HTML-Kit updates.
Updates" in your installation of HTML-Kit, it can be added by installing hkSetupPlus.
Updates" tab and press Enter. A wizard for installing the plugin will appear with more information. Once you give the go-ahead, it'll automatically install the plugin for you.