Livezilla API Wordpress plugin

We have Livezilla Chat in use based on Wordpress ([login to view URL]). Since the javascript opens a new window, if users click on it, this process is not according to webstandard compliant ([login to view URL]). There is one other solution, without to enter only the Javascript code in the text widget in Wordpress. (Or in a template page). Namely, with API. We want a plugin for Wordpress, (upload within wp-content/plugin) so this may also be presented at Wordpress website ([login to view URL]) and is updated when new versions of Wordpress. (new order).