Trying to modify the value of a CSAction, dependent on the v

[Kaylub]

I'm kind of an idiot when it comes to javascript, so sorry if this question seems stupid. Is it possible to change the value of a csaction using javascript?

I'm trying to change the link value of a new window when the csaction opens the new window.

My csaction looks like this:
<csactions>
<csaction name="186f68c67" class="Open Window" type="onevent" val0="../../USER_DOWNLOADS/Recording%20Artists%20Manual%20E.mpg" val1="_blank" val2="800" val3="600" val4="true" val5="true" val6="true" val7="true" val8="true" val9="true" val10="true" urlparams="1"></csaction>
</csactions>
<csscriptdict import="import">
<script type="text/javascript" src="../../css/CSScriptLib.js"></script>
</csscriptdict>
<csactiondict>
<script type="text/javascript"><!--
CSAct[/*CMP*/ '186f68c67'] = new Array(CSOpenWindow,/*URL*/ '../../USER_DOWNLOADS/Recording%20Artists%20Manual%20E.mpg','_blank',800,600,true,true,true,true,true,true,true);


So anyways, I was wondering, is it possible to change the link location using a javascript function I could call when the user mouses over the button depending on the value of "infoReady"?
I know this is completely wrong, but is ANYTHING at all like the following possible?:
Or does anyone have another idea?

Here's the example i had in mind, (the incorrect one, but the one I'm using as an example of what I'm trying to accomplish).
function MovieChooser() {
var Navigator=document.formRegister.infoReady.value
if (Navigator=="RAYes") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_A.mpg";}
if (Navigator=="RANo1") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_B.mpg";}
if (Navigator=="RANo2") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_C.mpg";}
if (Navigator=="RANo3") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_D.mpg";}
if (Navigator=="RANo4") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_E.mpg";}
if (Navigator=="RANo5") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_F.mpg";}
if (Navigator=="RANo6") {
document.csaction.186f68c67.val0 = "../../USER_DOWNLOADS/RecordingManual_G.mpg";}
}