The code that you are using works prior to fuji.

This code works with the scoped API and applies to custom and global applications on Fuji or later versions.

function sections() {

    return {

    'Widget': {

    'type': 'widgetname'

    }

    };

}

function render() {

    var scope = gs.getCurrentScopeName();

    scope = (scope == "rhino.global" ? "" : scope + "_");

    var page = renderer.getPreference('type');

    return renderer.getRenderedPage(scope + page);

}

function getEditLink() {

    var scope = gs.getCurrentScopeName();

    scope = (scope == "rhino.global" ? "" : scope + "_");

    var page = renderer.getPreference('type');

    return "sys_ui_page.do?sysparm_query=name=" + scope + page;

}

Check section 2 in the below page:

Using UI Pages as Gauges - ServiceNow Wiki