#1. With each license key, you only use for 1 domain website.
#2. Elementor Pro Plugin: We bought an extended license to be able include it in our theme, and we own only one license key (as well as in case with single license), theme buyers are not allowed to use that key. But, don’t worry, Plugin Elementor Pro still working in your site.
To update new version, please deactivate current plugin, download new plugin at http://source.wpopal.com/plugins/new/elementor-pro-3.x.zip and re-install