load Javascript asynchroniously inside Head-Tag including a timeout ?

Hi, A JavaScript is loaded Asynchronously inside the head section of various websites. We would like find a way to avoid the pittfalls of potential latencies. From time to time , if the js does dot deliver quickly enough, the pageload is delayed. race conditions are not the biggest problem - but we wish to avoid potential delay. Please find a find detailed jobdescription here: [login to view URL]