Hello cd_mackenzie,

I don't know what version of Infragistics you are using but if you have at least 8.1 you can use the new aikido webdialogwindow as a popup.  You can add a JavaScript listener for mouse move and capture the x and y positions of the mouse and show the dialog window at the mouse location.  The aspx page displayed in the webdialogwindow handles the update for the grid and has a button that has its OnClick attribute set to a JavaScript function.  This JavaScript function can reference a JavaScript function on the opening page by using the parent.thejavascriptfunction method.  In the JavaScript on the parent window you would simply cause a post back of the gird using:

igtbl_doPostBack('TheGridID');

Then hide the dialog window with:

var dialog = $find('TheDialogWindowID');

dialog.set_windowState($IG.DialogWindowState.Hidden);

Hope it helps,

Patrick

update:

Forgot to tell you to add a client side event for the mouse click or double click to show the dialog window.