did you try with javascript?
Code:
<script>
sec = 0;
function autoLaunch(delay) {
if (sec == delay)
location = "x-avefront://---.dream/proc/launch/1";
else
sec ++;
chrono=setTimeout("autoLaunch("+delay+")",1000);
}
</script>
<body onload=autoLaunch(3)>
i didnt test it but it should work