Trouble with Flex 3 PopupManager

I'm trying to use the PopupManager class in a Flex3 AIR app to open different kinds of panels but I'm running into some problems with it. I'm using a method like the following with which all panels are opened ..

private function createPopUp(clazz:Class, modal:Boolean = false):IFlexDisplayObject
{
 var p:IFle开发者_运维问答xDisplayObject = IFlexDisplayObject(PopUpManager.createPopUp(_windowParent, clazz, modal));
 PopUpManager.centerPopUp(p);
 return p;
}

_windowParent is a reference to the application's WindowedApplication root object. I'm running into two kinds of problems with this:

1. Not all popups appear modal, even if I set the modal parameter to true. This seems to happen if I open a popup panel from within another popup panel.

2. In some of the popup panels are ComboBoxes and the popdown menu of the comboboxes opens underneath of their parent panel (i.e. under the depth of the panel) so the menu of the combobox becomes partly or fully obstructed.

I've tried different parameters for the PopUpManager.createPopUp() childList parameter (e.g. PopUpManagerChildList.APPLICATION) but that did not change anything.

Hoping that anyone has some tips on these problems!

Nevermind! Figured out I some code that would change the depth of panels that was messing this up.