FlashPaper and UILoader acting strange

I've got a timeline with multiple frames. In tow of those frames, I have UI开发者_如何学CLoader which loads a FlashPaper SWF(different for each frame). When the user clicks on the button to navigate to one of them, that UILoader will properly load the FlashPaper. when the user selects the other item from the navigation, the other FlashPaper loads, but does not display properly. Instead, a black box appears over the content area. (It seems like the mask is not properly being applied to the FlashPaper SWF.) What could be wrong and how can I fix this?

I could not fix this. Instead, I changed one of my PDF files into XML (not directly - the PDF was originally an Excel file) and then I loaded it into a DataGrid.

I suspect that ti had to do with a FRAME_ENTER loop I was running that was calling "AddChild" in certain cases.