I have entered my license key. The update-plugin-button is then active but it only takes me to the wp-admin/plugin.php-page. There I can view details for the new version but there is no update-button. The bottom info line says: “There is a new version available – Automatic updates is not available for this plugin”
Regarding the listed domains, ACF will save the domains when you activated it. This way it can check which domains have the ability to update the plugin. Since you are using the Developer license, it shouldn’t affect you much.
If you want, you can open a new ticket about the “manage activations” issue.