Flex :: Internet Based App - Tooltips Not Displaying

I have a flex app that used to be an internet based app. In it I have a function that creates tooltip error messages when I tell it to create an error message. I pulled this app out verbatim to a desktop app and restructured things a bit to get it to run, but I did not mess with the core fundamentals of the mxml file that utilizes this aside from changing the root tag from a type of 's:Group' to 's:Window'. Everything runs correctly, but the tooltips are not displaying.

Here's the tooltip code (inline mxml code in the fx:script cdata tag):
import mx.controls.ToolTip;
import mx.managers.ToolTipManager;
public var errorTip:ToolTip;
private function createErrorMsg(errorMsg:String, object:Object):void {
if (errorTip){ToolTipManager.destroyToolTip(errorTip);
[Code] .....

Basically, I pass the function a string and an object (text input, checkbox, button, etc...etc...) and it positions it and displays the error message. This fully works in my web version, but not in my desktop version.

Here's the code that instantiates the window:
var window:LoginWindow = new LoginWindow();
Window.systemChrome = NativeWindowSystemChrome.NONE;
Window.transparent = true;
Window.open(true);
Window.maximize()

On a side note, I check to see if the errorTip exists at the beginning of the function and then destroy it so that the higher scoped variable 'errorTip' always equals the reference to the currently displayed error. This allows me to just destroy that error tip on form validation and then error check again, but it only allows one tooltip to be displayed at a time. Is there a better way to query the tooltip manager for all of it's currently displayed tooltips and destroy them all?