Autocomplete multi-select PHP Ajax

Have a script from here [login to view URL] that works fairly well. Want to modify it. Know just enough PHP and MySQL to be dangerous. Know almost no javascript. 1) For some reason, when I run this script and type a country like "Australia", if I hit the ENTER key, it shows the country twice. If I use the mouse, just once as it should. 2) Want to be able to POST values to another page, but not the country NAME. I want the country CODE. See [login to view URL] file and note the select query in fetch.php. 3) No access to a live database. But MySQL fields will be "country_code" and "country_name". I want "country_name" shown in autocomplete box, but "country_code" data to be posted to [login to view URL] page. 4) Would like to have MULTIPLE autocompletes on same page. One is the example here by COUNTRY, and maybe under that I'd like by LANGUAGE. So in that case, "language_name" and "language_code" would be in the database (i.e. "EN"=>"English", "FR"=>"French", etc). Want to SEE the full names in the autocomplete boxes, but post the code. I hope that all makes sense. If you need to do it your own way and not this script, that's fine. All I want are TWO autocomplete boxes on one page that posts the "keys" for the autocompleted data from both tables. Preferably in two arrays (country, languages). Thanks