Check to see if a cfwindow exists
When a window gets created by <cfwindow> coldfusion gives it a unique name and not the name you assigned it.
I have found a work around in the way of checking for the title of the window as when you create a cfwindow the window title div get the id of yourwinname_title.

Example javascript
<cfajaximport tags="cfwindow"/>
<script language="javascript">
function createphloadwin() {
if(document.getElementById('mywindow_title')) {
var x = "true";
// Show the window"mywindow");
} else {
var x = "false";
// Create a new window
ColdFusion.Window.create("mywindow", "Upload Photos", "", {height:250,width:400,closable:true,draggable:true,resizable:false,center:true,initshow:true,modal:t rue })
// Put your content in the window or you can assign the url in the ColdFusion.Window.create()
document.getElementById('mywindow_body').innerHTML = 'My Window content';

<a href="javascript:createphloadwin();">Check for window</a>

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