>So the difference with the original flexigrid code and new one is that in the original the trSelected seemed to attach when I selected a row with the mouse. Right now this class only attaches after I click on the row. That's the difference and that's why that code didn't work.
>

If you're not actually letting them edit all the selected items (that is, you're just editing the item they double-clicked on), why not just grab the object reference that is passed when the dblclick() event is called, ex:

$('#flexClients').dblclick(function (e) {
   var id = $(e.target).attr('id')';
   // id should contain the row id
});